The Truth about Extreme Exercise, Oxidative Stress, and Your Health

Intense athletics like Ironman triathlons damage your body, but this same damage may make you stronger.

If you’re a committed athlete and health nut, you’ve probably heard it said that your training may be endangering your health.

More often than not, the article or video (or sales page) will claim that the oxidative stress caused by your intense training is increasing your risk of heart disease and cancer, making you age faster, and possibly, causing you to die sooner.(1-3)

The idea is that intense training produces more free radicals than moderate exercise, which may “overwhelm antioxidant defenses” and cause “irreparable oxidative damage… potentially resulting in ill health and/or disease,” writes Dr. Kelsey Fisher-Wellman, the author of a review published in 2009.(4)

Before we dive into the evidence, let’s examine what oxidative stress is.

Oxidative Stress: A Quick Primer

During normal metabolism, your body produces unstable molecules, free radicals being the most common. These molecules can damage your cells and create more free radicals, causing more damage.

Your body uses different antioxidants to control free radical (oxidative) damage. The two main kinds of antioxidants are endogenous (produced inside your body) and exogenous (consumed from diet and other sources).

When free radicals overwhelm your antioxidant defenses, your cells are damaged. This damage is called oxidative stress.(5,6)

There’s still some question as to whether or not oxidative stress accelerates aging.(7-11) However, most data indicate that excessive and chronic oxidative stress may cause cellular damage and contribute to atherosclerosis, heart disease, cancer, dementia, and many other diseases.(12-18)

Why Oxidative Stress Isn’t Always Bad

When we first discovered that free radicals existed in humans, they were quickly blamed for aging and other diseases.(19)

Contrary to what researchers first thought, we now know that oxidative stress is beneficial in small amounts. In fact, it’s essential. Newer research has shown that oxidative stress prompts your cells to become stronger over time by increasing your body’s antioxidants.(20)

Free radicals also serve as important signaling molecules for a number of functions in your body, so getting rid of them entirely would likely be counterproductive.(21) 

All forms of exercise cause some oxidative stress.(22) This is probably one of the reasons it makes you healthier. Your body is slightly weakened, recovers, and becomes more resistant to oxidative stress from the next workout (or other stressors).(23-30)

Most researchers agree that moderate exercise produces healthy amounts of oxidative stress, to the point they call it an antioxidant.(31)

The concern is that doing more than that may have the opposite effect.

When Exercise May Be too Much of a Good Thing

Your body has a limited capacity to increase its antioxidants and control free radicals.

Some researchers believe that long, intense exercise (especially endurance training) may cause more oxidative stress than humans can handle.(32)

“Heavy and sustained exercise training generates large quantities of free-radicals that likely outstrip the buffering capacity of the system, leaving these individuals susceptible to oxidative stress…” writes Harshal R. Patil, the author of a recent review on this topic.(33)

This is thought to be true “even in superbly trained individuals.”(34)

In theory, your body runs out of antioxidants during extreme exercise. Free radicals overwhelm your cells and oxidative stress rises far beyond healthy levels. Over time, this damage increases your risk of heart disease, cancer, and an early death.

Dr. James O’Keefe, the author of a review on how endurance exercise affects heart health, states it this way:(35)

“If we went out for a run right now and you ran hard… by 60 minutes something starts happening… the free radicals blossom, and it starts burning the heart. It starts searing and inflaming the inside of your coronary arteries.”(36)

Every athlete has a limit to how much oxidative stress they can handle. The question is whether or not extreme exercise can push your body past this point.

Before we look at the research, let’s define “extreme” exercise.

What is “Extreme” Exercise?

If you ask most researchers in this field, the answer will probably be “whatever causes lots of oxidative damage.”

The problem with with this definition is that any kind of exercise can cause oxidative damage.(37) If your training is challenging, it’s probably causing significant oxidative stress, regardless of your sport.(38)

This is true for:

  • Strength training.(39-42)
  • Sprinting.(43)
  • Motocross.(44)
  • Indoor rock climbing.(45)
  • Running.(46-49)
  • Cycling.(50-53)
  • Swimming.(54)
  • Rowing.(55,56)
  • Kayaking.(57,58)
  • Canoeing.(59)
  • Soccer.(60,61)
  • Tennis.(62)
  • Football.(63,64)
  • Rugby.(65,66)
  • Handball.(67)
  • Martial arts.(68,69)
  • Volleyball.(70,71)

Some limited data also indicates that oxidative stress may contribute to fatigue. If this is the case, it’s possible that any workout that can make you tired will probably cause some oxidative damage.(72)

Is Endurance Exercise Especially Bad?

Endurance sports often get the most blame for being “extreme” or “excessive” when it comes to oxidative stress.

Mitochondria (the “power plants” of cells) are believed to be one of the main sources of free radicals. Endurance sports use more oxygen, which sends more energy through your mitochondria. In theory, the higher your metabolic rate and energy needs, the more free radicals your mitochondria will produce.(73,74)

However, free radicals are also created through other pathways, and are not always related to your oxygen needs.(75) Several studies have shown that despite much higher oxygen intakes during aerobic exercise, anaerobic exercise (sprinting, weight lifting, etc) can produce similar levels of oxidative damage.(76,77)

Studies that didn’t measure oxygen consumption have also found similar levels of oxidative damage after strength and endurance training.(78,79)

That said, it’s generally possible to do more endurance training, which will probably create more free radicals over time. No athlete runs sprints for six hours straight, but many pro cyclists ride their bikes that long every day.

On the other hand, there are a lot of bodybuilders, football players, and other physique or mixed sport athletes who train several hours a day.

For the rest of the article, we’ll loosely define “extreme” exercise as anything that has you working at a moderate to high intensity for more than about 1-2 hours per day, endurance or not, endurance or otherwise.

Now let’s see if this kind of training is bad for you.

What the Evidence Says About Extreme Exercise and Oxidative Stress

Despite many inconsistencies and problems with the research, most data indicate that hard exercise increases oxidative stress.(80-84)

However, long-term studies, as opposed to short-term, have shown that extreme training can increase your body’s antioxidant levels which can help prevent and repair oxidative damage.(85-88)

According to Dr. Karl-Heinz Wagner, “during exercise… ROS [free radicals] formation can stimulate adaptive mechanisms… which can lead to decreased oxidative damage or apoptosis [cell death],” in a review published in 2011.(89)

In one study, untrained people ran five times per week, for an hour at a time, at  80% of their maximum heart rates (basically, the definition of “chronic cardio”). There was an increase in lipid peroxidation and oxidative stress at the beginning of the study. Twelve weeks later, however, the runners had less lipid peroxidation, higher antioxidant levels, and less oxidative stress than before the study.(90)

Most people wouldn’t call five hours per week of running “extreme,” but other studies have shown the same adaptations can occur with much more training.

With consistent training, the “capacity of the body will expand or adapt; ultimately leading to improvements in health and/or human performance,” continues Dr. Wagner.

Endurance athletes are able to prevent or at least minimize oxidative stress after races and brutal training periods. The rise in oxidative stress is moderate to nonexistent, and usually goes back to normal hours or days later.(91-103)

Oxidative damage sometimes occurs, but it’s minimal.(104) It’s also repaired quickly and most data indicate there is no lasting harm.(105,106)

Multiple studies have shown that after Ironman triathlons, well-trained athletes have a large decline in DNA damage for about three weeks.(107-109) The researchers believe this is thanks to “the upregulation of repair mechanisms and enhanced endogenous antioxidative systems.”(110)

In other words, their training increased their body’s ability to prevent and repair DNA damage, largely by increasing its antioxidant defenses.

DNA damage tends to decline after an Ironman in well-trained athletes. This is because training increases your body’s antioxidants and DNA repair mechanisms.

It’s also likely this boost in antioxidant defenses protects against oxidative stress from “non-exercise related conditions.”(111)

That is, if you get stuck in an elevator with someone reeking of cigarettes, your body will probably suffer less damage than if you weren’t training like nuts.

Animal studies have also shown that exhaustive and moderate exercise helps increase antioxidant levels and protect against oxidative stress.(112-117)

Elite endurance athletes (who train more than almost anyone) also tend to live longer than the average population, although it’s impossible to tell if this is from better antioxidant protection or other reasons.(118-120)

That said, at least one study has found higher levels of oxidative damage in well-trained endurance athletes at rest.(121)

This is misleading, however, because the athletes had done a hard race two days before being tested, and it’s possible this wasn’t enough time for them to recover. Even so, they were better protected against some markers of oxidative stress after exercise than healthy non-athletes.

Most other studies have also shown similar or lower levels of oxidative stress in athletes compared to healthy non-athletes.(122,123)

Before you decide to do an Ironman or become Mr. Olympia however, understand that boosting your antioxidant levels often requires a lot of training.

How Much Should You Train to Protect Your Body?

This depends on what you’re training for.

If you exercise only for health, you don’t need to train three hours a day to be well protected against oxidative stress.

Moderate endurance and strength training can significantly reduce oxidative stress and increase your antioxidant defenses.(124-131)

It’s a different story if you’re a competitive athlete. You probably need to train more to protect yourself.

A low-volume training plan might be fine if your event is short, but it’s probably not best for longer or more intense competitions. It takes a lot of hard training to increase your antioxidant levels enough to protect you from something like an Ironman or marathon.(132)

“The training programme must be sufficiently long and intense to trigger a consequent adaptive response of the antioxidant system and a decrease of oxidative stress,” writes Dr. Julien Finaud, the author of a 2006 review.(133)

If you don’t train adequately, your antioxidant system may not be strong enough to protect you from permanent oxidative damage if you suddenly increase your training volume. In other words, being a “weekend warrior” may not be ideal.(134)

One study found a large increase in oxidative damage after a football game. The the researchers concluded that “higher amounts of physical activity may be required” to protect them from this kind of exercise.(135)

Athletes with the highest training volumes, experience, and fitness often have higher antioxidant levels and lower levels of oxidative stress.(136-138) Well-trained cyclists are also better able to minimize oxidative stress after a workout than amateurs.(139)

Small amounts of endurance training can also increase your Vo2max before it significantly raises your antioxidant levels.(140) Basically, you can get fitter without necessarily being better protected against oxidative stress.

In one of the studies mentioned previously, Ironman athletes were well protected against oxidative stress after training 13 hours per week.(141) Other data have shown that triathletes training 14-17 hours per week were able to manage the oxidative stress from their workouts.(142,143)

That’s a lot of training, but minimal considering it took these athletes around 10-12 hours to finish an Ironman.

If your training is consistent and specific to your sport, it will probably increase your antioxidant levels enough to protect you from excessive oxidative damage. 

Of course, you can still overdo your training.

How Much is Too Much?

Some authors have suggested that there is an “optimal level of exercise” and that  extreme training “exceeds the currently undefined optimal level.”(144)

The problem with this notion of an “optimal level of exercise” is that it’s relative to the individual and changes over time.

If an elite Ironman triathlete were to to do a two hour bike ride, they’d probably experience almost no oxidative stress. For them, that’s an easy workout.

If a couch potato who hasn’t exercised in 30 years were to do the same workout, it might cause far more damage.

Oxidative stress is not necessarily dependent on how much you exercise, but how much you do relative to your current ability level. 

In untrained people, intense, moderate, and light exercise all cause about the same amount of oxidative damage.(145)

Intense, moderate, and easy training all increase MDA levels (a marker of oxidative damage) about the same amount in untrained people.

According Dr. Niels Vollaard, the author of a review published in 2005, oxidative stress is “desired, or even a required consequence of exercise, which is controlled to such an extent that it occurs whenever the relative exercise intensity is sufficiently high, regardless of training status.”(146)

For example, professional cyclists often train over 1,000 hours per year — over 3 hours per day, and at times, 30-40 hours per week. Considering the demands of their sport, this might be “optimal.”

They tend to have higher antioxidant levels than amateur cyclists and healthy non-athletes. Their antioxidant levels are also increased at the end of a 20 day stage race, suggesting they handled the oxidative stress well.(147)

Other studies have also found that well-trained cyclists are able to control the  oxidative stress from intense training and racing.(148-151)

If you push yourself outside of your comfort zone, you’re probably going to experience some oxidative stress. If you do too much, you might hurt yourself. If you don’t do enough, you may not be protected from higher training loads and other sources of oxidative stress.

This process “can be seen as no different from other responses to exercise: a certain load disturbs homeostasis, resulting in adaptations in the body to be able to cope with a similar load in the future,” writes Dr. Vollaard.(152)

Some athletes beat themselves into the ground with too much volume, intensity, or both. In these cases, it’s possible oxidative stress may play a role in overtraining.(153,159)

Luckily, it’s usually not hard to tell when this is happening. Overtraining makes you sick, anxious, and moody. It destroys your sleep, performance, appetite, and libido. It also perpetuates sore or fatigued muscles, causes injuries, and usually makes you feel horrible.(160-163)

If that sounds familiar, you’re doing too much.

The Truth about Extreme Exercise, Oxidative Stress, and Your Health

Every kind of hard exercise creates free radicals that cause some oxidative damage.

This damage is quickly repaired, and sparks adaptations that make you more resistant to oxidative damage from high volume and/or intensity training.

With more training, your body increases its antioxidant levels to control the additional free radicals, generally keeping oxidative stress within safe limits.

It’s possible to hurt yourself by overtraining, and oxidative stress may be part of this process. However, it’s not news that overtraining is bad for you. High volume training is also not the same thing as overtraining.

If you train smart by providing enough stimulus to progress, but not so much that you overtrain, the oxidative stress from your training will probably not damage your health.

At present, “there are no indications that exercise-induced oxidative stress has any negative impact on health…,” according to Dr. Vollaard.(164)

As with fatigue, muscle soreness, and any other response to exercise, oxidative stress should not be avoided, but managed with smart, consistent training.

You don’t need to do extreme athletics to be healthy.

On the other hand, if you do train hours a day for extreme sports, you probably don’t have to worry about it damaging your health or shortening your life. It might even make you healthier.

Most evidence indicates that if you train in a progressive, intelligent manner, with adequate recovery between workouts, you can build up to extremely high training loads and still be protected against potentially dangerous levels of oxidative stress.

You’re reading Part 5 of a series on whether or not exercise damages your heart. Click here to read Part 6.

You can read the first post in this series by clicking here.

A special thanks to Drs. Monica Pittaluga, Richard Bloomer, Hilmi Orhan, and Zsolt Radak for their assistance in making this article possible.

 

References

1. Fisher-Wellman K, Bloomer RJ. Acute exercise and oxidative stress: a 30 year history. Dyn Med. 2009 Jan 13;8:1. doi: 10.1186/1476-5918-8-1. Abstract: https://pmid.us/19144121 | Full Text: https://goo.gl/QMo47

2. Patil HR, O’keefe JH, Lavie CJ, et al. Cardiovascular damage resulting from chronic excessive endurance exercise. Mo Med. 2012 Jul-Aug;109(4):312-21. Abstract: https://pmid.us/22953596 | Full Text: https://goo.gl/pxtJj | Author Contact: <jokeefe@saint-lukes.org>

3. O’keefe JH, Patil HR, Lavie CJ, et al. Potential adverse cardiovascular effects from excessive endurance exercise. Mayo Clin Proc. 2012;87(6):587-95. Abstract: https://pmid.us/22677079 | Full Text: https://goo.gl/Q5MmQ

4. Fisher-Wellman K, Bloomer RJ. Acute exercise and oxidative stress: a 30 year history. Dyn Med. 2009 Jan 13;8:1. doi: 10.1186/1476-5918-8-1. Abstract: https://pmid.us/19144121 | Full Text: https://goo.gl/QMo47

5. Palomero J, Jackson MJ. Redox regulation in skeletal muscle during contractile activity and aging. J Anim Sci. 2010 Apr;88(4):1307-13. doi: 10.2527/jas.2009-2436. Epub 2009 Oct 9. Abstract: https://pmid.us/19820047 | Full Text: https://goo.gl/c0Vum

6. Radak Z, Zhao Z, Koltai E, et al. Oxygen Consumption and Usage During Physical Exercise: The Balance Between Oxidative Stress and ROS-Dependent Adaptive Signaling. Antioxid Redox Signal. 2012 Nov 16. Abstract: https://pmid.us/22978553 | Full Text: Received from author.

7. Pérez VI, Bokov A, Van Remmen H, et al. Is the oxidative stress theory of aging dead? Biochim Biophys Acta. 2009 Oct;1790(10):1005-14. doi: 10.1016/j.bbagen.2009.06.003. Epub 2009 Jun 11. Abstract: https://pmid.us/19524016 | Full Text: https://goo.gl/GQAKC

8. Muller FL, Lustgarten MS, Jang Y, et al. Trends in oxidative aging theories. Free Radic Biol Med. 2007 Aug 15;43(4):477-503. Epub 2007 Apr 10. Abstract: https://pmid.us/17640558 | Full Text: https://goo.gl/eBw53

9. Speakman JR, Selman C. The free-radical damage theory: Accumulating evidence against a simple link of oxidative stress to ageing and lifespan. Bioessays. 2011 Apr;33(4):255-9. doi: 10.1002/bies.201000132. Epub 2011 Feb 2. Abstract: https://pmid.us/21290398 | Full Text: NA

10. Sanz A, Stefanatos RK. The mitochondrial free radical theory of aging: a critical view. Curr Aging Sci. 2008 Mar;1(1):10-21. Abstract: https://pmid.us/20021368 | Full Text: https://goo.gl/N4bzW

11. Gruber J, Schaffer S, Halliwell B. The mitochondrial free radical theory of ageing–where do we stand? Front Biosci. 2008 May 1;13:6554-79. Abstract: https://pmid.us/18508680 | Full Text: NA

12. Gray K, Bennett M. Role of DNA damage in atherosclerosis–bystander or participant? Biochem Pharmacol. 2011 Oct 1;82(7):693-700. Epub 2011 Jun 24. Abstract: https://pmid.us/21726542 | Full Text: NA

13. Andreassi MG. DNA damage, vascular senescence and atherosclerosis. J Mol Med (Berl). 2008 Sep;86(9):1033-43. Epub 2008 Jun 19. Abstract: https://pmid.us/18563380 | Full Text: NA

14. Singh U, Jialal I. Oxidative stress and atherosclerosis. Pathophysiology. 2006 Aug;13(3):129-42. Epub 2006 Jun 6. Abstract: https://pmid.us/16757157 | Full Text: NA

15. Reuter S, Gupta SC, Chaturvedi MM, et al. Oxidative stress, inflammation, and cancer: how are they linked? Free Radic Biol Med. 2010 Dec 1;49(11):1603-16. doi: 10.1016/j.freeradbiomed.2010.09.006. Epub 2010 Sep 16. Abstract: https://pmid.us/20840865 | Full Text: https://goo.gl/IO76E

16. Bonomini F, Tengattini S, Fabiano A, et al. Atherosclerosis and oxidative stress. Histol Histopathol. 2008 Mar;23(3):381-90. Abstract: https://pmid.us/18072094 | Full Text: NA

17. Schnabel R, Blankenberg S. Oxidative stress in cardiovascular disease: successful translation from bench to bedside? Circulation. 2007 Sep 18;116(12):1338-40. Abstract: https://pmid.us/17875978 | Full Text: https://goo.gl/oCsPe

18. Bennett S, Grant MM, Aldred S. Oxidative stress in vascular dementia and Alzheimer’s disease: a common pathology. J Alzheimers Dis. 2009;17(2):245-57. doi: 10.3233/JAD-2009-1041. Abstract: https://pmid.us/19221412 | Full Text: NA

19. Harman D. Aging: a theory based on free radical and radiation chemistry. J Gerontol. 1956 Jul;11(3):298-300. Abstract: https://pmid.us/13332224 | Full Text: https://goo.gl/UmWU1

20. Radak Z, Chung HY, Koltai E, et al. Exercise, oxidative stress and hormesis. Ageing Res Rev. 2008 Jan;7(1):34-42. Epub 2007 Aug 2. Abstract: https://pmid.us/17869589 | Full Text: https://goo.gl/A6G99

21. Dröge W. Free radicals in the physiological control of cell function. Physiol Rev. 2002 Jan;82(1):47-95. Abstract: https://pmid.us/11773609 | Full Text: https://goo.gl/Xd03i

22. Fisher-Wellman K, Bloomer RJ. Acute exercise and oxidative stress: a 30 year history. Dyn Med. 2009 Jan 13;8:1. doi: 10.1186/1476-5918-8-1. Abstract: https://pmid.us/19144121 | Full Text: https://goo.gl/QMo47

23. Radak Z, Chung HY, Goto S. Exercise and hormesis: oxidative stress-related adaptation for successful aging. Biogerontology. 2005;6(1):71-5. Abstract: https://pmid.us/15834665 | Full Text: https://goo.gl/E8dsS

24. Radak Z, Chung HY, Koltai E, et al. Exercise, oxidative stress and hormesis. Ageing Res Rev. 2008 Jan;7(1):34-42. Epub 2007 Aug 2. Abstract: https://pmid.us/17869589 | Full Text: https://goo.gl/A6G99

25. Radak Z, Chung HY, Goto S. Systemic adaptation to oxidative challenge induced by regular exercise. Free Radic Biol Med. 2008 Jan 15;44(2):153-9. doi: 10.1016/j.freeradbiomed.2007.01.029. Epub 2007 Jan 23. Abstract: https://pmid.us/18191751 | Full Text: Received from author.

26. Majerczak J, Rychlik B, Grzelak A, et al. Effect of 5-week moderate intensity endurance training on the oxidative stress, muscle specific uncoupling protein (UCP3) and superoxide dismutase (SOD2) contents in vastus lateralis of young, healthy men. J Physiol Pharmacol. 2010 Dec;61(6):743-51. Abstract: https://pmid.us/21224506 | Full Text: https://goo.gl/pFHwB

27. Radak Z, Zhao Z, Koltai E, et al. Oxygen Consumption and Usage During Physical Exercise: The Balance Between Oxidative Stress and ROS-Dependent Adaptive Signaling. Antioxid Redox Signal. 2012 Nov 16. Abstract: https://pmid.us/22978553 | Full Text: Received from author.

28. Knez WL, Coombes JS, Jenkins DG. Ultra-endurance exercise and oxidative damage: implications for cardiovascular health. Sports Med. 2006;36(5):429-41. Abstract: https://pmid.us/16646630 | Full Text: https://goo.gl/Xn3yt

29. Morton JP, Kayani AC, McArdle A, et al. The exercise-induced stress response of skeletal muscle, with specific emphasis on humans. Sports Med. 2009;39(8):643-62. Abstract: http:/pmid.us/19769414 | Full Text: NA

30. Nikolaidis MG, Paschalis V, Giakas G,et al. Decreased blood oxidative stress after repeated muscle-damaging exercise. Med Sci Sports Exerc. 2007 Jul;39(7):1080-9. Abstract: https://pmid.us/17596775 | Full Text: https://goo.gl/4Fbae

31. Gomez-Cabrera MC, Domenech E, Viña J. Moderate exercise is an antioxidant: upregulation of antioxidant genes by training. Free Radic Biol Med. 2008 Jan 15;44(2):126-31. doi: 10.1016/j.freeradbiomed.2007.02.001. Epub 2007 Feb 9. Abstract: https://pmid.is/18191748 | Full Text: https://goo.gl/xemYR

32. Radak Z, Chung HY, Koltai E, et al. Exercise, oxidative stress and hormesis. Ageing Res Rev. 2008 Jan;7(1):34-42. Epub 2007 Aug 2. Abstract: https://pmid.us/17869589 | Full Text: https://goo.gl/A6G99

33. Patil HR, O’keefe JH, Lavie CJ, et al. Cardiovascular damage resulting from chronic excessive endurance exercise. Mo Med. 2012 Jul-Aug;109(4):312-21. Abstract: https://pmid.us/22953596 | Full Text: https://goo.gl/pxtJj | Author Contact: <jokeefe@saint-lukes.org>

34. Radak Z, Chung HY, Koltai E, et al. Exercise, oxidative stress and hormesis. Ageing Res Rev. 2008 Jan;7(1):34-42. Epub 2007 Aug 2. Abstract: https://pmid.us/17869589 | Full Text: https://goo.gl/A6G99

35. O’keefe JH, Patil HR, Lavie CJ, et al. Potential adverse cardiovascular effects from excessive endurance exercise. Mayo Clin Proc. 2012;87(6):587-95. Abstract: https://pmid.us/22677079 | Full Text: https://goo.gl/Q5MmQ

36. TEDxTalks. Run for Your Life! At a comfortable pace, and not too far: James O’Keefe at TEDxUMKC [Video] [7:51]. Published November 27, 2012. Accessed December 13, 2012. https://goo.gl/D521F

37. Fisher-Wellman K, Bloomer RJ. Acute exercise and oxidative stress: a 30 year history. Dyn Med. 2009 Jan 13;8:1. doi: 10.1186/1476-5918-8-1. Abstract: https://pmid.us/19144121 | Full Text: https://goo.gl/QMo47

38. Morton JP, Kayani AC, McArdle A, et al. The exercise-induced stress response of skeletal muscle, with specific emphasis on humans. Sports Med. 2009;39(8):643-62. Abstract: http:/pmid.us/19769414 | Full Text: NA

39. Zembron-Lacny A, Ostapiuk J, Slowinska-Lisowska M, et al. Pro-antioxidant ratio in healthy men exposed to muscle-damaging resistance exercise. J Physiol Biochem. 2008 Mar;64(1):27-35. Abstract: https://pmid.us/18663993 | Full Text: NA

40. Paschalis V, Nikolaidis MG, Fatouros IG, et al. Uniform and prolonged changes in blood oxidative stress after muscle-damaging exercise. In Vivo. 2007 Sep-Oct;21(5):877-83. Abstract: https://pmid.us/18019428 | Full Text: https://goo.gl/VYcIu

41. Deminice R, Sicchieri T, Mialich MS, et al. Oxidative stress biomarker responses to an acute session of hypertrophy-resistance traditional interval training and circuit training. J Strength Cond Res. 2011 Mar;25(3):798-804. doi: 10.1519/JSC.0b013e3181c7bac6. Abstract: https://pmid.us/20581699 | Full Text: NA

42. Deminice R, Sicchieri T, Payão PO, et al. Blood and salivary oxidative stress biomarkers following an acute session of resistance exercise in humans. Int J Sports Med. 2010 Sep;31(9):599-603. doi: 10.1055/s-0030-1255107. Epub 2010 Jul 8. Abstract: https://pmid.us/20617486 | Full Text: NA

43. Bloomer RJ, Goldfarb AH. Anaerobic exercise and oxidative stress: a review. Can J Appl Physiol. 2004;29:245–263. Abstract: https://pmid.us/15199226 | Full text: NA

44. Ascensão A, Ferreira R, Marques F, et al. Effect of off-road competitive motocross race on plasma oxidative stress and damage markers. Br J Sports Med. 2007 Feb;41(2):101-5. Epub 2006 Nov 30. Abstract: https://pmid.us/17138632 | Full Text: https://goo.gl/DxZiV

45. Magalhães J, Ferreira R, Marques F, et al. Indoor climbing elicits plasma oxidative stress. Med Sci Sports Exerc. 2007 Jun;39(6):955-63. Abstract: https://pmid.us/17545885

46. Nikolaidis MG, Jamurtas AZ, Paschalis V, et al. The effect of muscle-damaging exercise on blood and skeletal muscle oxidative stress: magnitude and time-course considerations. Sports Med. 2008;38(7):579-606. Abstract: https://pmid.us/18557660 | Full Text: NA

47. Tsai K, Hsu TG, Hsu KM, et al. Oxidative DNA damage in human peripheral leukocytes induced by massive aerobic exercise. Free Radic Biol Med. 2001 Dec 1;31(11):1465-72. Abstract: https://pmid.us/11728819 | Full Text: NA

48. Child RB, Wilkinson DM, Fallowfield JL, et al. Elevated serum antioxidant capacity and plasma malondialdehyde concentration in response to a simulated half-marathon run. Med Sci Sports Exerc. 1998 Nov;30(11):1603-7. Abstract: https://pmid.us/9813873 | Full Text: NA

49. Liu ML, Bergholm R, Mäkimattila S, et al. A marathon run increases the susceptibility of LDL to oxidation in vitro and modifies plasma antioxidants. Am J Physiol. 1999 Jun;276(6 Pt 1):E1083-91. Abstract: https://pmid.us/10362621 | Full Text: https://goo.gl/eXUMx

50. Muñoz Marín D, Olcina G, Timón R, et al. Effect of different exercise intensities on oxidative stress markers and antioxidant response in trained cyclists. J Sports Med Phys Fitness. 2010 Mar;50(1):93-8. Abstract: https://pmid/20308979 | Full Text: NA

51. Sureda A, Tauler P, Aguiló A, et al. Relation between oxidative stress markers and antioxidant endogenous defences during exhaustive exercise. Free Radic Res. 2005 Dec;39(12):1317-24. Abstract: https://pmid.us/16298861 | Full Text: NA

52. Tauler P, Sureda A, Cases N, et al. Increased lymphocyte antioxidant defences in response to exhaustive exercise do not prevent oxidative damage. J Nutr Biochem. 2006 Oct;17(10):665-71. Epub 2005 Nov 28. Abstract: https://pmid.us/16481153 | Full Text: https://goo.gl/KG5zT

53. Martarelli D, Pompei P. Oxidative stress and antioxidant changes during a 24-hours mountain bike endurance exercise in master athletes. J Sports Med Phys Fitness. 2009 Mar;49(1):122-7. Abstract: https://pmid.us/19188905

54. Deminice R, Trindade CS, Degiovanni GC, et al. Oxidative stress biomarkers response to high intensity interval training and relation to performance in competitive swimmers. J Sports Med Phys Fitness. 2010 Sep;50(3):356-62. Abstract: https://pmid.us/20842099 | Full Text: NA

55. Kyparos A, Riganas C, Nikolaidis MG, et al. The effect of exercise-induced hypoxemia on blood redox status in well-trained rowers. Eur J Appl Physiol. 2012 Jun;112(6):2073-83. doi: 10.1007/s00421-011-2175-x. Epub 2011 Sep 27. Abstract: https://pmid.us/21947454 | Full Text: https://goo.gl/y0vfC

56. Kyparos A, Vrabas IS, Nikolaidis MG, et al. Increased oxidative stress blood markers in well-trained rowers following two thousand-meter rowing ergometer race. J Strength Cond Res. 2009 Aug;23(5):1418-26. doi: 10.1519/JSC.0b013e3181a3cb97. Abstract: https://pmid.us/19620924 | Full Text: NA

57. Teixeira V, Valente H, Casal S, et al. Antioxidant status, oxidative stress, and damage in elite trained kayakers and canoeists and sedentary controls. Int J Sport Nutr Exerc Metab. 2009 Oct;19(5):443-56. Abstract: https://pmid.us/19910648 | Full Text: NA

58. Teixeira V, Valente H, Casal S, et al. Antioxidant status, oxidative stress, and damage in elite kayakers after 1 year of training and competition in 2 seasons. Appl Physiol Nutr Metab. 2009 Aug;34(4):716-24. doi: 10.1139/H09-062. Abstract: https://pmid.us/19767808 | Full Text: NA

59. Teixeira V, Valente H, Casal S, et al. Antioxidant status, oxidative stress, and damage in elite trained kayakers and canoeists and sedentary controls. Int J Sport Nutr Exerc Metab. 2009 Oct;19(5):443-56. Abstract: https://pmid.us/19910648 | Full Text: NA

60. Fatouros IG, Chatzinikolaou A, Douroudos II, et al. Time-course of changes in oxidative stress and antioxidant status responses following a soccer game. J Strength Cond Res. 2010 Dec;24(12):3278-86. doi: 10.1519/JSC.0b013e3181b60444. Abstract: https://pmid.us/19996787 | Full Text: NA

61. Ascensão A, Rebelo A, Oliveira E, et al. Biochemical impact of a soccer match – analysis of oxidative stress and muscle damage markers throughout recovery. Clin Biochem. 2008 Jul;41(10-11):841-51. doi: 10.1016/j.clinbiochem.2008.04.008. Epub 2008 Apr 23. Abstract: https://pmid.us/18457670 | Full Text: NA

62. Kyparos A, Salonikidis K, Nikolaidis MG, et al. Short duration exhaustive aerobic exercise induces oxidative stress: a novel play-oriented volitional fatigue test. J Sports Med Phys Fitness. 2007 Dec;47(4):483-90. Abstract: https://pmid.us/18091691 | Full Text: NA

63. Rudarli Nalçakan G, Nalçakan M, Var A, et al. Acute oxidative stress and antioxidant status responses following an American football match. J Sports Med Phys Fitness. 2011 Sep;51(3):533-9. Abstract: https://pmid.us/21904294 | Full Text: NA

64. Schippinger G, Wonisch W, Abuja PM, et al. Lipid peroxidation and antioxidant status in professional American football players during competition. Eur J Clin Invest. 2002 Sep;32(9):686-92. Abstract: https://pmid.us/12486869 | Full Text: NA

65. Chang CK, Tseng HF, Hsuuw YD, et al. Higher LDL oxidation at rest and after a rugby game in weekend warriors. Ann Nutr Metab. 2002;46(3-4):103-7. Abstract: https://pmid.us/12169852 | Full Text: NA

66. Finaud J, Scislowski V, Lac G, et al. Antioxidant status and oxidative stress in professional rugby players: evolution throughout a season. Int J Sports Med. 2006 Feb;27(2):87-93. Abstract: https://pmid.us/16475052 | Full Text: NA

67. Marin DP, Macedo dos Santos RC, Bolin AP. Cytokines and Oxidative Stress Status Following a Handball Game in Elite Male Players. Oxid Med Cell Longev. 2011; 2011: 804873. Full Text: https://goo.gl/yhar9

68. Pesić S, Jakovljević V, Cubrilo D, et al. [Oxidative status evaluation in elite karate athletes during training process]. [Article in Serbian]. Vojnosanit Pregl. 2009 Jul;66(7):551-5. Abstract: https://pmid.us/19678580 | Full Text: NA

69. Pesic S, Jakovljevic V, Djordjevic D, et al. Exercise-induced changes in redox status of elite karate athletes. Chin J Physiol. 2012 Feb 29;55(1):8-15. doi: 10.4077/CJP.2012.AMM102. Abstract: https://pmid.us/22242949 | Full Text: NA

70. Martinovic J, Dopsaj V, Dopsaj MJ, et al. Long-term effects of oxidative stress in volleyball players. Int J Sports Med. 2009 Dec;30(12):851-6. doi: 10.1055/s-0029-1238289. Abstract: https://pmid.us/20013555 | Full Text: NA

71. Martinović J, Dopsaj V, Kotur-Stevuljević J, et al. Oxidative stress biomarker monitoring in elite women volleyball athletes during a 6-week training period. J Strength Cond Res. 2011 May;25(5):1360-7. Abstract: https://pmid.us/21157395 | Full Text: NA

72. Vollaard NB, Shearman JP, Cooper CE. Exercise-induced oxidative stress: myths, realities and physiological relevance. Sports Med. 2005;35(12):1045-62. Abstract: https://pmid.us/16336008 | Full Text: https://goo.gl/hTQaS

73. Radak Z, Zhao Z, Koltai E, et al. Oxygen Consumption and Usage During Physical Exercise: The Balance Between Oxidative Stress and ROS-Dependent Adaptive Signaling. Antioxid Redox Signal. 2012 Nov 16. Abstract: https://pmid.us/22978553 | Full Text: Received from author.

74. Fisher-Wellman K, Bloomer RJ. Acute exercise and oxidative stress: a 30 year history. Dyn Med. 2009 Jan 13;8:1. doi: 10.1186/1476-5918-8-1. Abstract: https://pmid.us/19144121 | Full Text: https://goo.gl/QMo47

75. Ji LL. Antioxidants and oxidative stress in exercise. Proc Soc Exp Biol Med. 1999 Dec;222(3):283-92. Abstract: https://pmid.us/10601887 | Full Text: https://goo.gl/bKVQT

76. Alessio HM, Hagerman AE, Fulkerson BK, et al. Generation of reactive oxygen species after exhaustive aerobic and isometric exercise. Med Sci Sports Exerc. 2000 Sep;32(9):1576-81. Abstract: https://pmid.us/10994907 | Full Text: https://goo.gl/2vxth

77. Shi M, Wang X, Yamanaka T, et al. Effects of anaerobic exercise and aerobic exercise on biomarkers of oxidative stress. Environ Health Prev Med. 2007 Sep;12(5):202-8. doi: 10.1265/ehpm.12.202. Abstract: https://pmid.us/21432082 | Full Text: https://goo.gl/HMt0I

78. Bloomer RJ, Goldfarb AH, Wideman L, et al. Effects of acute aerobic and anaerobic exercise on blood markers of oxidative stress. J Strength Cond Res. 2005 May;19(2):276-85. Abstract: https://pmid.us/15903362 | Full Text: https://goo.gl/fE5Hc

79. Fisher-Wellman K, Bloomer RJ. Acute exercise and oxidative stress: a 30 year history. Dyn Med. 2009 Jan 13;8:1. doi: 10.1186/1476-5918-8-1. Abstract: https://pmid.us/19144121 | Full Text: https://goo.gl/QMo47

80. Vollaard NB, Shearman JP, Cooper CE. Exercise-induced oxidative stress: myths, realities and physiological relevance. Sports Med. 2005;35(12):1045-62. Abstract: https://pmid.us/16336008 | Full Text: https://goo.gl/hTQaS | Author Contact: <N.Vollaard@hw.ac.uk>

81. Fisher-Wellman K, Bloomer RJ. Acute exercise and oxidative stress: a 30 year history. Dyn Med. 2009 Jan 13;8:1. doi: 10.1186/1476-5918-8-1. Abstract: https://pmid.us/19144121 | Full Text: https://goo.gl/QMo47

82. Knez WL, Coombes JS, Jenkins DG. Ultra-endurance exercise and oxidative damage: implications for cardiovascular health. Sports Med. 2006;36(5):429-41. Abstract: https://pmid.us/16646630 | Full Text: https://goo.gl/Xn3yt

83. König D, Neubauer O, Nics L, et al. Biomarkers of exercise-induced myocardial stress in relation to inflammatory and oxidative stress. Exerc Immunol Rev. 2007;13:15-36. Abstract: https://pmid.us/18198658 | Full Text: https://goo.gl/eZxr0

84. Clarkson PM, Thompson HS. Antioxidants: what role do they play in physical activity and health? Am J Clin Nutr 2000;72:637 – 46. Abstract: https://pmid.us/10919970 | Full Text: https://goo.gl/B35Cv

85. Wagner KH, Reichhold S, Neubauer O. Impact of endurance and ultraendurance exercise on DNA damage. Ann N Y Acad Sci. 2011 Jul;1229:115-23. doi: 10.1111/j.1749-6632.2011.06106.x. Abstract: http:/pmid.us/21793846 | Full Text: https://goo.gl/1YlBW

86. Knez WL, Jenkins DG, Coombes JS. Oxidative stress in half and full Ironman triathletes. Med Sci Sports Exerc. 2007 Feb;39(2):283-8. Abstract: https://pmid.us/17277592 | Full Text: https://goo.gl/5uqlb

87. Knez WL, Coombes JS, Jenkins DG. Ultra-endurance exercise and oxidative damage: implications for cardiovascular health. Sports Med. 2006;36(5):429-41. Abstract: https://pmid.us/16646630 | Full Text: https://goo.gl/Xn3yt

88. Vollaard NB, Shearman JP, Cooper CE. Exercise-induced oxidative stress: myths, realities and physiological relevance. Sports Med. 2005;35(12):1045-62. Abstract: https://pmid.us/16336008 | Full Text: https://goo.gl/hTQaS | Author Contact: <N.Vollaard@hw.ac.uk>

89. Wagner KH, Reichhold S, Neubauer O. Impact of endurance and ultraendurance exercise on DNA damage. Ann N Y Acad Sci. 2011 Jul;1229:115-23. doi: 10.1111/j.1749-6632.2011.06106.x. Abstract: http:/pmid.us/21793846 | Full Text: https://goo.gl/1YlBW

90. Miyazaki H, Oh-ishi S, Ookawara T, et al. Strenuous endurance training in humans reduces oxidative stress following exhausting exercise. Eur J Appl Physiol. 2001 Jan-Feb;84(1-2):1-6. Abstract: https://pmid.us/11394236 | Full Text: NA

91. Wagner KH, Reichhold S, Hölzl C, et al. Well-trained, healthy triathletes experience no adverse health risks regarding oxidative stress and DNA damage by participating in an ultra-endurance event. Toxicology. 2010 Dec 5;278(2):211-6. doi: 10.1016/j.tox.2009.09.006. Epub 2009 Sep 18. Abstract: https://pmid.us/19766696 | Full Text: Requested.

92. Aguiló A, Tauler P, Fuentespina E, et al. Antioxidant response to oxidative stress induced by exhaustive exercise. Physiol Behav. 2005 Jan 31;84(1):1-7. Epub 2004 Nov 10. Abstract: https://pmid.us/15642600 | Full Text: https://goo.gl/6Q3Rq

93. Reichhold S, Neubauer O, Veronika E, et al. No acute and persistent DNA damage after an Ironman triathlon. Cancer Epidemiol Biomarkers Prev. 2008 Aug;17(8):1913-9. Abstract: https://pmid.us/18708380 | Full Text: https://goo.gl/YYqbC

94. Reichhold S, Neubauer O, Hoelzl C, et al. DNA damage in response to an Ironman triathlon. Free Radic Res. 2009 Aug;43(8):753-60. doi: 10.1080/10715760903040628. Abstract: https://pmid.us/19591014 | Full Text: NA

95. Cases N, Sureda A, Maestre I, et al. Response of antioxidant defences to oxidative stress induced by prolonged exercise: antioxidant enzyme gene expression in lymphocytes. Eur J Appl Physiol. 2006 Oct;98(3):263-9. Epub 2006 Aug 9. Abstract: https://pmid.us/16896722 | Full Text: NA

96. Margaritis I, Tessier F, Richard MJ, et al. No evidence of oxidative stress after a triathlon race in highly trained competitors. Int J Sports Med. 1997 Apr;18(3):186-90. Abstract: https://pmid.us/9187972 | Full Text: NA

97. Shing CM, Peake JM, Ahern SM, et al. The effect of consecutive days of exercise on markers of oxidative stress. Appl Physiol Nutr Metab. 2007 Aug;32(4):677-85. Abstract: https://pmid.us/17622282 | Full Text: https://goo.gl/4CguF

98. Serrano E, Venegas C, Escames G, et al. Antioxidant defence and inflammatory response in professional road cyclists during a 4-day competition. J Sports Sci. 2010 Aug;28(10):1047-56. Abstract: https://pmid.us/20686993 | Full Text: NA

99. Kabasakalis A, Kyparos A, Tsalis G, et al. Blood oxidative stress markers after ultramarathon swimming. J Strength Cond Res. 2011 Mar;25(3):805-11. doi: 10.1519/JSC.0b013e3181d0b109. Abstract: https://pmid.us/20613649 | Full Text: NA

100. Okamura K, Doi T, Hamada K, et al. Effect of repeated exercise on urinary 8-hydroxy-deoxyguanosine excretion in humans. Free Radic Res. 1997 Jun;26(6):507-14. Abstract: https://pmid.us/9212344 | Full Text: NA

101. Neubauer O, Reichhold S, Nersesyan A, et al. Exercise-induced DNA damage: is there a relationship with inflammatory responses? Exerc Immunol Rev. 2008;14:51-72. Abstract: https://pmid.us/19203084 | Full Text: https://goo.gl/s0fhs

102. Knez WL, Jenkins DG, Coombes JS. Oxidative stress in half and full Ironman triathletes. Med Sci Sports Exerc. 2007 Feb;39(2):283-8. Abstract: https://pmid.us/17277592 | Full Text: https://goo.gl/5uqlb

103. Tong TK, Lin H, Lippi G, et al. Serum oxidant and antioxidant status in adolescents undergoing professional endurance sports training. Oxid Med Cell Longev. 2012;2012:741239. doi: 10.1155/2012/741239. Epub 2012 Apr 17. Abstract: https://pmid.us/22577491 | Full Text: https://goo.gl/5v58a

104. Serrano E, Venegas C, Escames G, et al. Antioxidant defence and inflammatory response in professional road cyclists during a 4-day competition. J Sports Sci. 2010 Aug;28(10):1047-56. Abstract: https://pmid.us/20686993 | Full Text: NA

105. Neubauer O, Reichhold S, Nersesyan A, et al. Exercise-induced DNA damage: is there a relationship with inflammatory responses? Exerc Immunol Rev. 2008;14:51-72. Abstract: https://pmid.us/19203084 | Full Text: https://goo.gl/s0fhs

106. Wagner KH, Reichhold S, Neubauer O. Impact of endurance and ultraendurance exercise on DNA damage. Ann N Y Acad Sci. 2011 Jul;1229:115-23. doi: 10.1111/j.1749-6632.2011.06106.x. Abstract: http:/pmid.us/21793846 | Full Text: https://goo.gl/1YlBW

107. Reichhold S, Neubauer O, Veronika E, et al. No acute and persistent DNA damage after an Ironman triathlon. Cancer Epidemiol Biomarkers Prev. 2008 Aug;17(8):1913-9. Abstract: https://pmid.us/18708380 | Full Text: https://goo.gl/YYqbC<

108. Reichhold S, Neubauer O, Hoelzl C, et al. DNA damage in response to an Ironman triathlon. Free Radic Res. 2009 Aug;43(8):753-60. doi: 10.1080/10715760903040628. Abstract: https://pmid.us/19591014 | Full Text: NA

109. Wagner KH, Reichhold S, Hölzl C, et al. Well-trained, healthy triathletes experience no adverse health risks regarding oxidative stress and DNA damage by participating in an ultra-endurance event. Toxicology. 2010 Dec 5;278(2):211-6. doi: 10.1016/j.tox.2009.09.006. Epub 2009 Sep 18. Abstract: https://pmid.us/19766696 | Full Text: Requested.

110. Reichhold S, Neubauer O, Veronika E, et al. No acute and persistent DNA damage after an Ironman triathlon. Cancer Epidemiol Biomarkers Prev. 2008 Aug;17(8):1913-9. Abstract: https://pmid.us/18708380 | Full Text: https://goo.gl/YYqbC

111. Fisher-Wellman K, Bloomer RJ. Acute exercise and oxidative stress: a 30 year history. Dyn Med. 2009 Jan 13;8:1. doi: 10.1186/1476-5918-8-1. Abstract: https://pmid.us/19144121 | Full Text: https://goo.gl/QMo47

112. Oztasan N, Taysi S, Gumustekin K, et al. Endurance training attenuates exercise-induced oxidative stress in erythrocytes in rat. Eur J Appl Physiol. 2004 May;91(5-6):622-7. Epub 2003 Dec 18. Abstract: https://pmid.us/14685869 | Full Text: NA

113. Taysi S, Oztasan N, Efe H, et al. Endurance training attenuates the oxidative stress due to acute exhaustive exercise in rat liver. Acta Physiol Hung. 2008 Dec;95(4):337-47. doi: 10.1556/APhysiol.95.2008.4.2. Abstract: https://pmid.us/19009910 | Full Text: NA

114. Aksoy Y, Yapanoğlu T, Aksoy H, et al. Effects of endurance training on antioxidant defense mechanisms and lipid peroxidation in testis of rats. Arch Androl. 2006 Jul-Aug;52(4):319-23. Abstract: https://pmid.us/16728348 | Full Text: NA

115. Leeuwenburgh C, Heinecke JW. Oxidative stress and antioxidants in exercise. Curr Med Chem. 2001 Jun;8(7):829-38. Abstract: https://pmid.us/11375753 | Full Text: https://goo.gl/BABc3

116. Goto S, Radák Z. Hormetic effects of reactive oxygen species by exercise: a view from animal studies for successful aging in human. Dose Response. 2009 Dec 14;8(1):68-72. doi: 10.2203/dose-response.09-044. Abstract: https://pmid.us/20221292 | Full Text: https://goo.gl/crO8U

117. Fisher-Wellman K, Bloomer RJ. Acute exercise and oxidative stress: a 30 year history. Dyn Med. 2009 Jan 13;8:1. doi: 10.1186/1476-5918-8-1. Abstract: https://pmid.us/19144121 | Full Text: https://goo.gl/QMo47

118. Teramoto M, Bungum TJ. Mortality and longevity of elite athletes. J Sci Med Sport. 2010 Jul;13(4):410-6. doi: 10.1016/j.jsams.2009.04.010. Epub 2009 Jul 1. Abstract: https://pmid.us/19574095 | Full Text: https://goo.gl/Maal6

119. Sanchis-Gomar F, Olaso-Gonzalez G, Corella D, et al. Increased average longevity among the “Tour de France” cyclists. Int J Sports Med. 2011 Aug;32(8):644-7. doi: 10.1055/s-0031-1271711. Epub 2011 May 26. Abstract: https://pmid.us/21618162 | Full Text: NA

120. Reimers CD, Knapp G, Reimers AK. Does physical activity increase life expectancy? A review of the literature. J Aging Res. 2012;2012:243958. doi: 10.1155/2012/243958. Epub 2012 Jul 1. Abstract: https://pmid.us/22811911 | Full Text: https://goo.gl/3u0jC

121. Pittaluga M, Parisi P, Sabatini S, et al. Cellular and biochemical parameters of exercise-induced oxidative stress: relationship with training levels. Free Radic Res. 2006 Jun;40(6):607-14. Abstract: https://pmid.us/16753838 | Full Text: Received from author.

122. Knez WL, Jenkins DG, Coombes JS. Oxidative stress in half and full Ironman triathletes. Med Sci Sports Exerc. 2007 Feb;39(2):283-8. Abstract: https://pmid.us/17277592 | Full Text: https://goo.gl/5uqlb

123. Knez WL, Jenkins DG, Coombes JS. Oxidative stress in half and full Ironman triathletes. Med Sci Sports Exerc. 2007 Feb;39(2):283-8. Abstract: https://pmid.us/17277592 | Full Text: https://goo.gl/5uqlb

124. Cakir-Atabek H, Demir S, PinarbaŞili RD, et al. Effects of different resistance training intensity on indices of oxidative stress. J Strength Cond Res. 2010 Sep;24(9):2491-7. doi: 10.1519/JSC.0b013e3181ddb111. Abstract: https://pmid.us/20802287 | Full Text: NA

125. Vincent HK, Bourguignon C, Vincent KR. Resistance training lowers exercise-induced oxidative stress and homocysteine levels in overweight and obese older adults. Obesity (Silver Spring). 2006 Nov;14(11):1921-30. Abstract: https://pmid.us/17135607 | Full Text: NA

126. Radak Z, Chung HY, Koltai E, et al. Exercise, oxidative stress and hormesis. Ageing Res Rev. 2008 Jan;7(1):34-42. Epub 2007 Aug 2. Abstract: https://pmid.us/17869589 | Full Text: https://goo.gl/A6G99

127.  Radak Z, Chung HY, Goto S. Exercise and hormesis: oxidative stress-related adaptation for successful aging. Biogerontology. 2005;6(1):71-5. Abstract: https://pmid.us/15834665 | Full Text: https://goo.gl/E8dsS

128. Radak Z, Chung HY, Goto S. Systemic adaptation to oxidative challenge induced by regular exercise. Free Radic Biol Med. 2008 Jan 15;44(2):153-9. doi: 10.1016/j.freeradbiomed.2007.01.029. Epub 2007 Jan 23. Abstract: https://pmid.us/18191751 | Full Text: Received from author.

129. Majerczak J, Rychlik B, Grzelak A, et al. Effect of 5-week moderate intensity endurance training on the oxidative stress, muscle specific uncoupling protein (UCP3) and superoxide dismutase (SOD2) contents in vastus lateralis of young, healthy men. J Physiol Pharmacol. 2010 Dec;61(6):743-51. Abstract: https://pmid.us/21224506 | Full Text: https://goo.gl/pFHwB

130. Campbell PT, Gross MD, Potter JD, et al. Effect of exercise on oxidative stress: a 12-month randomized, controlled trial. Med Sci Sports Exerc. 2010 Aug;42(8):1448-53. doi: 10.1249/MSS.0b013e3181cfc908. Abstract: https://pmid.us/20139793 | Full Text: https://goo.gl/PcLYx

131. Fatouros IG, Jamurtas AZ, Villiotou V, et al. Oxidative stress responses in older men during endurance training and detraining. Med Sci Sports Exerc. 2004 Dec;36(12):2065-72. Abstract: https://pmid.us/15570141 | Full Text: https://goo.gl/kY7lK

132. Finaud J, Lac G, Filaire E. Oxidative stress: relationship with exercise and training. Sports Med. 2006;36(4):327-58. Abstract: https://pmid.us/16573358 | Full Text: https://goo.gl/zH48t

133. Finaud J, Lac G, Filaire E. Oxidative stress: relationship with exercise and training. Sports Med. 2006;36(4):327-58. Abstract: https://pmid.us/16573358 | Full Text: https://goo.gl/zH48t

134. Chang CK, Tseng HF, Hsuuw YD, et al. Higher LDL oxidation at rest and after a rugby game in weekend warriors. Ann Nutr Metab. 2002;46(3-4):103-7. Abstract: https://pmid.us/12169852 | Full Text: NA

135. Rudarli Nalçakan G, Nalçakan M, Var A, et al. Acute oxidative stress and antioxidant status responses following an American football match. J Sports Med Phys Fitness. 2011 Sep;51(3):533-9. Abstract: https://pmid.us/21904294 | Full Text: NA

136. Margaritis I, Tessier F, Richard MJ, et al. No evidence of oxidative stress after a triathlon race in highly trained competitors. Int J Sports Med. 1997 Apr;18(3):186-90. Abstract: https://pmid.us/9187972 | Full Text: NA

137.  Martinovic J, Dopsaj V, Dopsaj MJ, et al. Long-term effects of oxidative stress in volleyball players. Int J Sports Med. 2009 Dec;30(12):851-6. doi: 10.1055/s-0029-1238289. Abstract: https://pmid.us/20013555 | Full Text: NA

138. Knez WL, Jenkins DG, Coombes JS. Oxidative stress in half and full Ironman triathletes. Med Sci Sports Exerc. 2007 Feb;39(2):283-8. Abstract: https://pmid.us/17277592 | Full Text: https://goo.gl/5uqlb

139. Mena P, Maynar M, Gutierrez JM, et al. Erythrocyte free radical scavenger enzymes in bicycle professional racers. Adaptation to training. Int J Sports Med. 1991 Dec;12(6):563-6. Abstract: https://pmid.us/1797698 | Full Text: NA

140. Finaud J, Lac G, Filaire E. Oxidative stress: relationship with exercise and training. Sports Med. 2006;36(4):327-58. Abstract: https://pmid.us/16573358 | Full Text: https://goo.gl/zH48t

141. Reichhold S, Neubauer O, Veronika E, et al. No acute and persistent DNA damage after an Ironman triathlon. Cancer Epidemiol Biomarkers Prev. 2008 Aug;17(8):1913-9. Abstract: https://pmid.us/18708380 | Full Text: https://goo.gl/YYqbC

142. Knez WL, Jenkins DG, Coombes JS. Oxidative stress in half and full Ironman triathletes. Med Sci Sports Exerc. 2007 Feb;39(2):283-8. Abstract: https://pmid.us/17277592 | Full Text: https://goo.gl/5uqlb

143. Knez WL, Coombes JS, Jenkins DG. Ultra-endurance exercise and oxidative damage: implications for cardiovascular health. Sports Med. 2006;36(5):429-41. Abstract: https://pmid.us/16646630 | Full Text: https://goo.gl/Xn3yt

144. Fisher-Wellman K, Bloomer RJ. Acute exercise and oxidative stress: a 30 year history. Dyn Med. 2009 Jan 13;8:1. doi: 10.1186/1476-5918-8-1. Abstract: https://pmid.us/19144121 | Full Text: https://goo.gl/QMo47

145. Moflehi D, Kok LY, Tengku-Kamalden TF, et al. Effect of single-session aerobic exercise with varying intensities on lipid peroxidation and muscle-damage markers in sedentary males. Glob J Health Sci. 2012 May 23;4(4):48-54. doi: 10.5539/gjhs.v4n4p48. Abstract: https://pmid.us/22980341 | Full Text: https://goo.gl/FbLpa

146. Vollaard NB, Shearman JP, Cooper CE. Exercise-induced oxidative stress: myths, realities and physiological relevance. Sports Med. 2005;35(12):1045-62. Abstract: https://pmid.us/16336008 | Full Text: https://goo.gl/hTQaS | Author Contact: <N.Vollaard@hw.ac.uk>

147. Mena P, Maynar M, Gutierrez JM, et al. Erythrocyte free radical scavenger enzymes in bicycle professional racers. Adaptation to training. Int J Sports Med. 1991 Dec;12(6):563-6. Abstract: https://pmid.us/1797698 | Full Text: NA

148. Shing CM, Peake JM, Ahern SM, et al. The effect of consecutive days of exercise on markers of oxidative stress. Appl Physiol Nutr Metab. 2007 Aug;32(4):677-85. Abstract: https://pmid.us/17622282 | Full Text: https://goo.gl/4CguF

149. Serrano E, Venegas C, Escames G, et al. Antioxidant defence and inflammatory response in professional road cyclists during a 4-day competition. J Sports Sci. 2010 Aug;28(10):1047-56. Abstract: https://pmid.us/20686993 | Full Text: NA

150. Aguiló A, Tauler P, Fuentespina E, et al. Antioxidant response to oxidative stress induced by exhaustive exercise. Physiol Behav. 2005 Jan 31;84(1):1-7. Epub 2004 Nov 10. Abstract: https://pmid.us/15642600 | Full Text: https://goo.gl/6Q3Rq

151. Tong TK, Lin H, Lippi G, et al. Serum oxidant and antioxidant status in adolescents undergoing professional endurance sports training. Oxid Med Cell Longev. 2012;2012:741239. doi: 10.1155/2012/741239. Epub 2012 Apr 17. Abstract: https://pmid.us/22577491 | Full Text: https://goo.gl/5v58a

152. Vollaard NB, Shearman JP, Cooper CE. Exercise-induced oxidative stress: myths, realities and physiological relevance. Sports Med. 2005;35(12):1045-62. Abstract: https://pmid.us/16336008 | Full Text: https://goo.gl/hTQaS | Author Contact: <N.Vollaard@hw.ac.uk>

153. Schippinger G, Fankhauser F, Abuja PM, et al. Competitive and seasonal oxidative stress in elite alpine ski racers. Scand J Med Sci Sports. 2009 Apr;19(2):206-12. Abstract: https://pmid.us/18266792 | Full Text: NA

154. Palazzetti S, Richard MJ, Favier A, et al. Overloaded training increases exercise-induced oxidative stress and damage. Can J Appl Physiol. 2003 Aug;28(4):588-604. Abstract: https://pmid.us/12904636 | Full Text: NA

155. Tanskanen M, Atalay M, Uusitalo A. Altered oxidative stress in overtrained athletes. J Sports Sci. 2010 Feb;28(3):309-17. doi: 10.1080/02640410903473844. Abstract: https://pmid.us/20077275 | Full Text: NA

156. Finaud J, Lac G, Filaire E. Oxidative stress: relationship with exercise and training. Sports Med. 2006;36(4):327-58. Abstract: https://pmid.us/16573358 | Full Text: https://goo.gl/zH48t

157. Fisher-Wellman K, Bloomer RJ. Acute exercise and oxidative stress: a 30 year history. Dyn Med. 2009 Jan 13;8:1. doi: 10.1186/1476-5918-8-1. Abstract: https://pmid.us/19144121 | Full Text: https://goo.gl/QMo47

158. Breitbach S, Tug S, Simon P. Circulating cell-free DNA: an up-coming molecular marker in exercise physiology. Sports Med. 2012 Jul 1;42(7):565-86. doi: 10.2165/11631380-000000000-00000. Abstract: https://pmid.us/22694348 | Full Text: NA

159. Margonis K, Fatouros IG, Jamurtas AZ, et al. Oxidative stress biomarkers responses to physical overtraining: implications for diagnosis. Free Radic Biol Med. 2007 Sep 15;43(6):901-10. Epub 2007 May 23. Abstract: https://pmid.us/17697935 | Full Text: NA

160. Cosca DD, Navazio F. Common problems in endurance athletes. Am Fam Physician. 2007 Jul 15;76(2):237-44. Abstract: https://pmid.us/17695568 | Full Text: https://goo.gl/CDSvP

161. Johnson MB, Thiese SM. A review of overtraining syndrome-recognizing the signs and symptoms. J Athl Train. 1992;27(4):352-4. Abstract: https://pmid.us/16558192 | Full Text: https://goo.gl/NzFWf

162. Budgett R. Fatigue and underperformance in athletes: the overtraining syndrome. Br J Sports Med. 1998 June; 32(2): 107–110. Abstract: https://goo.gl/64LsZ | Full Text: https://goo.gl/p74aj

163. Halson SL, Jeukendrup AE. Does overtraining exist? An analysis of overreaching and overtraining research. Sports Med. 2004;34(14):967-81. Abstract: https://pmid.us/15571428 | Full Text: https://goo.gl/uu8Bn

164. Vollaard NB, Shearman JP, Cooper CE. Exercise-induced oxidative stress: myths, realities and physiological relevance. Sports Med. 2005;35(12):1045-62. Abstract: https://pmid.us/16336008 | Full Text: https://goo.gl/hTQaS | Author Contact: <N.Vollaard@hw.ac.uk>

3 Comments

  1. Dr.Jagan Mohan Sidda on December 28, 2017 at 3:24 am

    Informative article… Very useful..

  2. Han-Lin on January 8, 2018 at 8:37 pm

    It makes more sense why we shouldn’t skip base training.

    HR and power meters can help you avoid overtraining. It’s possible to exercise for long duration at the low end of zone 3 or lower without overtraining. That means biking 3 hours to and from work shouldn’t be too tiring.

  3. Greg on November 19, 2018 at 6:15 pm

    I’m an ex-stressed out executive in my 60s now into 6 months of regular and what I consider pretty intense exercise. I do 1 hour to 90 minutes resistance raining on one day followed by 30 mintues HIIT on the other days. Notwithstanding the fact that I feel the best I’ve felt since I was a teenager, I came to this site because my wife was worried I might be overdoing it. Thanks for the advice – I will be printing this out for her to be reassured!

Leave a Comment