Quick Hit Summary
Vitamin E is a fat soluble antioxidant that protects cell membranes and lipid structures (LDL cholesterol, etc) from oxidative damage. Many researchers have examined the potential role that vitamin E may have in limiting exercise induced oxidative damage. Currently, there is a lack of scientific evidence to support an ergogenic role for vitamin E when taken alone. There are a few studies that suggest that the use of vitamin E as part of a multi vitamin-mineral complex may be effective at reducing a few markers post exercise oxidation in untrained resistance trained athletes and male endurance athletes completing ultra-marathon competitions.
Antioxidants
Previously, I described the general relationship between free radicals, antioxidants and oxidative damage. If you have not read the article Understanding Antioxidants, Free Radicals and Oxidative Damage, I’d recommend taking a quick look as it may help you understand the terminology used in this multipart series looking at dietary antioxidants. First up on the board —> Vitamin E!
Vitamin E
The chemical structure of α-tocopherol, the most bioavailable form of vitamin-E13.
As one of the fat soluble vitamins, vitamin E works in cell membranes (which are composed of fatty acids) and other lipid structures (LDL cholesterol, etc) that are susceptible to free radical damage.
Vitamin E & Athletic Performance
Endurance Training
With the increased production of reactive oxygen species (ROS) during exercise, one would naturally assume that vitamin E supplementation may limit excessive oxidative damage. Taken as a whole, most of the research does not support the use of vitamin E supplementation in endurance trained individuals1. However, research conducted by Mastaloudis et al. indicated that supplements containing vitamin E and C, may be effective at preventing oxidative damage in those participating in extreme endurance events. In a study carried out by Mastaloudis et al., antioxidant supplements (300 mg vitamin E; 1000 mg vitamin C) or placebos were given to 22 endurance runners (mean age 39, 11 men, 11 women)2. The runners took their respective supplements for 6 weeks leading up to a ~30 mile ultramarathon. Immediately post-race, increased oxidative damage was seen in those taking the placebos (5 women, 5 men) vs those receiving the antioxidant supplements (6 women, 6 men). These differences remained for up to 6 days post race in males. In contrast, all female runners had similar levels of oxidative damage 2 hours post race regardless of if they had taken the supplement or not. It’s hypothesized that women may have recovered faster from the race due to the presence of the sex hormone estradiol, which has proven antioxidant effects3. Interestingly, despite reducing oxidative damage to lipids, no significant differences were found in markers of inflammation between the two groups2.
Machefer et al. examined the effects of taking a vitamin E containing multivitamin-mineral supplement (containing 150 mg of vitamin C; 36 IU of vitamin E and numerous other vitamins and minerals) in 17 individuals (16 male; 1 female) preparing for a 7 day, 156 mile ultramathon4. For 3 weeks prior to and during the race, 10 individuals took the supplement while 7 received the placebo. On day 3 of the race, results indicated that those receiving the supplement had lower markers of inflammation than those receiving placebo. Interestingly, by day 7 there was no difference between the groups. The researchers hypothesized that this was due increases in the natural enzymes produced endogenously (ie-by the body) in response to the oxidative stress.
There has been one study that has looked at the physiological effects brought upon by long term antioxidant supplement usage. Aguiló et al. studied the impacts of supplementing 15 endurance trained athletes with an antioxidant supplement (500 mg/d vitamin E & 30 mg/d beta-carotene for all 90 days + 1g/d vitamin C for last 15 days) or a placebo for 90 days5. Physiological relevant performance measurements obtained both before and after 90 day period included maximal blood lactate concentration, %VO2max obtained during the aerobic-anaerobic transition area. After the 3 month posttest, those taking the antioxidants (vs placebo) significantly decreased maximal blood lactate concentration and increased %VO2max at the aerobic-anaerobic transition area. In other words, supplementation allowed them to rely upon a higher percentage of fat for energy, preserving their glycogen stores while cycling at submaximal exercise intensities.
Resistance Training
Currently, there is little evidence to support the claim that vitamin E supplementation alone reduces oxidative stress following a resistance training session. There have been a few studies indicating that a combination of antioxidants, including vitamin E, may be effective at reducing losses in muscle strength6 and markers of inflammation7. Despite these effects, both studies reported that post workout muscle soreness was the same regardless of if they took the supplement or the placebo. One thing that should be noted is that these studies were conducted in UNTRAINED individuals. Numerous studies have proven that with training, the body naturally adapts to the increased oxidative stress by producing natural antioxidant enzyme systems capable of handling ROS8. Other studies in untrained individuals have failed to show that vitamin E supplementation alone has any protective benefits on markers of muscle damage, muscle torque (rotational strength)9, or oxidative stress10.
Various studies have looked at benefits of vitamin E supplementation in seasoned resistance TRAINED individuals. McBride et al. looked at the effects of supplementing resistance trained men (mean age: 21-22 years; lifting experience > 1 year) with 1200 IU of vitamin E11. Participants completed a full body circuit training routine that was based off their 1 and 10 rep max. Measurements of various inflammatory and oxidative damage markers were obtained pre-exercise, 0 (ie-immediately after exercise), 6, 24, and 48 hours post exercising. Results showed no difference between placebo and vitamin E supplementation at any time point with respect to oxidative damage. A difference in the inflammatory marker of interest was only seen 24 hrs post exercise. Similar results in oxidative damage have also been seen in a more recent study12.
Bottom Line
When given alone, there is little evidence to support the idea that vitamin E supplementation is an effective approach for limiting exercise induced oxidative damage. This has been observed in both resistance and endurance training studies. A few studies have indicated that Vitamin E, as part of a multi vitamin-mineral supplement reduces markers of oxidative damage. However, even these results have been inconsistent.
Stay tuned for the conclusion of this article when we examine dietary sources of vitamin E as well as it’s in preventing heart health, cancer, and Alzheimer’s disease.
Reference
1 Viitala P, Newhouse IJ. Vitamin E supplementation, exercise and lipid peroxidation in human participants. Eur J Appl Physiol. 2004 Oct;93(1-2):108-15.
2 Mastaloudis A, Morrow JD, Hopkins DW, Devaraj S, Traber MG. Antioxidant supplementation prevents exercise-induced lipid peroxidation, but not inflammation, in ultramarathon runners. Free Radic Biol Med. 2004 May 15;36(10):1329-41.
3 Borrás C, Gambini J, López-Grueso R, Pallardó FV, Viña J. Direct antioxidant and protective effect of estradiol on isolated mitochondria. Biochim Biophys Acta. 2009 Sep 12. [Epub ahead of print].
4 Machefer G, Groussard C, Vincent S, Zouhal H, Faure H, Cillard J, Radák Z, Gratas-Delamarche A. Multivitamin-mineral supplementation prevents lipid peroxidation during “the Marathon des Sables”. J Am Coll Nutr. 2007 Apr;26(2):111-20.
5 Aguiló A, Tauler P, Sureda A, Cases N, Tur J, Pons A. Antioxidant diet supplementation enhances aerobic performance in amateur sportsmen. J Sports Sci. 2007 Sep;25(11):1203-10.
6 Shafat A, Butler P, Jensen RL, Donnelly AE. Effects of dietary supplementation with vitamins C and E on muscle function during and after eccentric contractions in humans. Eur J Appl Physiol. 2004 Oct;93(1-2):196-202. Epub 2004 Aug 7.
7 Phillips T, Childs AC, Dreon DM, Phinney S, Leeuwenburgh C. A dietary supplement attenuates IL-6 and CRP after eccentric exercise in untrained males. Med Sci Sports Exerc. 2003 Dec;35(12):2032-7.
8 Ji LL. Modulation of skeletal muscle antioxidant defense by exercise: Role of redox signaling. Free Radic Biol Med. 2008 Jan 15;44(2):142-52.
9 Beaton LJ, Allan DA, Tarnopolsky MA, Tiidus PM, Phillips SM. Contraction-induced muscle damage is unaffected by vitamin E supplementation. Med Sci Sports Exerc. 2002 May;34(5):798-805.
10 Viitala PE, Newhouse IJ, LaVoie N, Gottardo C. The effects of antioxidant vitamin supplementation on resistance exercise induced lipid peroxidation in trained and untrained participants. Lipids Health Dis. 2004 Jun 22;3:14.
11 McBride JM, Kraemer WJ, Triplett-McBride T, Sebastianelli W. Effect of resistance exercise on free radical production. Med Sci Sports Exerc. 1998 Jan;30(1):67-72.
12 Bloomer RJ, Falvo MJ, Schilling BK, Smith WA. Prior exercise and antioxidant supplementation: effect on oxidative stress and muscle injury. J Int Soc Sports Nutr. 2007 Oct 3;4:9.
13 Accessed June 13, 2010 from: http://en.wikipedia.org/wiki/Vitamin_e