Exercise-Induced Muscle Damage: Why Does It Happen? (And 5 Nutrition Solutions To Support Recovery)

Athletes train hard. They train almost every day, often twice a day, in order to be elite..

Does this mean athletes are constantly in a state of delayed-onset muscle soreness (DOMS) or fighting off excessive inflammation to effectively adapt to training to achieve their goals? Maybe. What about an athlete’s training phase, does that play a role? For example, if an athlete is optimizing for competition versus adapting to get bigger, stronger, or faster? 

What about recreational clients?

For many people, the sensation of mild to moderated delayed DOMS that creeps into your muscles 24-48 hours post-training is a sign of a good workout. You feel like you’ve trained and are making progress toward your goal. However, if it persists for more than 48 hours, if it limits your range of motion (ROM) or muscle function is it still helpful?

 Exercise-induced muscle damage (EIMD) is a complex and nuanced topic. 

A better question is when does exercise-induce muscle damage become so pronounced it requires specific nutrition strategies to mitigate the effects? I interviewed expert Dr. Daniel Owens PhD from Liverpool John Moore’s university to talk about his research in this area and what nutrition solutions you can turn to for evidence-based recovery support. 

First, let’s define exercise-induced muscle damage.

Listen to Daniel Owens PhD talk exercise-induced muscle damage on the Dr. Bubbs Performance Podcast!

Listen to Daniel Owens PhD talk exercise-induced muscle damage on the Dr. Bubbs Performance Podcast!

What Is Exercise-Induced Muscle Damage?

Exercise-induced muscle damage (EIMD) is characterized by symptoms that come on directly after training and persist for 1-5 days afterwards (although potentially all the way up to 14 days post-training). That’s a pretty wide margin, what happens if you get your training plan or recovery process wrong? 

For the athlete, the consequences of EIMD include is a direct effect on functional capacity (e.g. strength, range of motion, etc.), muscle soreness, muscle capacity and sense of force production and limb position.(1,2,3,4) How long and how intense these symptoms are for you depends on the intensity and duration of exercise and how your own individual susceptibility to the damaging stimulus of training.

For the athlete, loss of muscle function and increased muscle soreness likely have the greatest potential to negatively impact performance. 

Can targeted nutrition strategies help to offset these effects? Could this allow you to train more frequently or more intensely, thereby increasing the likelihood of achieving your goals? Or could it actually interfere with the recovery process? 

It’s a matter of balance; adequate training stress combined with sufficient recovery. Let’s take a deeper-dive into what causes exercise-induced muscle damage.

What Causes EMID?

Training of any type can cause exercise-induced muscle damage (EIMD), however there are a few types of training that may trigger greater muscle damage, such as; resistance training, prolonged or downhill running, and high-intensity interval training.(5,6,7,8)

Muscle damage is amplified during eccentric actions, particularly at longer muscle lengths, with greater forces, and faster angular velocities.(9,10,11) Interestingly, if you perform a training session with more eccentric loading, it may actually reduce the EMID in the subsequent sessions, a phenomenon known as the “rebound effect”. 

What are the underlying mechanisms that cause EMID? Let’s review.

#1 Primary Muscle Damage

Experts aren’t exactly sure the principle reason why eccentric training is more damaging to the muscle, however the consensus seems to be the mechanical loading during exercise.(12) Eccentric contractions have a lower motor unit activation compared to isometric and concentric contractions (when force is equal), putting an increased mechanical stress on a smaller number of muscle fibers during eccentric movements, and thus more muscle damage.(13)

#2 Secondary Muscle Damage

After the initial primary damage of training, a secondary effect occurs when calcium moves into cells, as the mitochondria attempt to maintain homeostasis.(14) The resultant inflammatory response is a crucial and natural process that clears away damage tissue, triggers tissue repair, and ultimately adaptation.

#3 Satellite Cell Activation

Muscle fiber recovery and regeneration requires the activation of muscle stem cells called satellite cells. Satellite cells are activated post-training, specifically in response to eccentric compared to concentric contractions.(15) The research highlights that sustained activation of satellite cells provides the muscle with the capacity to adapt more effectively from training.

To sum up, impaired muscle function, increased muscle soreness, elevated inflammatory levels and activation of satellite cells all play a role in exercise-induced muscle damage. 

What does all this mean for you the athlete?

 Nutritional strategies to target these areas - when used in the right context – may improve recovery from exercise-induced muscle damage. Let’s review five evidence-based nutrition strategies. 

Dietary Solutions for EIMD

Now you’ve understood the mechanisms underlying exercise-induced muscle damage (EIMD), you can better appreciate what nutritional interventions influence those mechanisms in order to exert a desired effect. 

There is a lot of nuance when it comes to application.

You don’t want to limit or buffer the exercise-induced stress and subsequent beneficial adaptations to training. The nutritional strategies we’ll discuss impact inflammation and oxidative stress – known to be important stimuli for adaptation - so it’s important to consider why you’re using them (i.e.  to cope with increased training volume and/or intensity) and when you’re using them (i.e. adaptation versus optimization phase).

The following are five potential evidence-based nutritional strategies.

#1 Protein

Protein is crucial to muscle protein synthesis and adaptation to resistance and endurance exercise.(16) Experts can’t say for sure whether protein around intense or damaging exercise can limit EIMD, but recent evidence suggests it can improve markers of muscle damage and accelerate recovery of force.(17,18) Aim for a protein intake of 0.2-0.5g/kg/meal around exercise, with bigger athletes trending toward the upper end of the range.

#2 Tart Cherry Juice

Dietary polyphenols are most commonly found in the diet via fruit, vegetable, tea and coffee consumption. Polyphenols have shown to exert significant antioxidant and anti-inflammatory effects, possessing the ability to attenuate cyclo-oxygenase (COX) 1 and 2 output to a similar degree compared to common, over-the-counter non-steroidal anti-inflammatory drugs (NSAIDs).(19,20) 

In particular, tart cherry juice stands out from the pack when it comes to recovery.

Research in resistance training using heavy eccentric bicep curls combined with two servings of tart cherry juice per day found an accelerated rate of recovery and reduced muscles soreness.(21) 

A key benefit to using a “food first” approach to performance nutrition is that it’s unlikely to interfere with the primary muscle damage response from exercise and thus not limit positive adaptation to training (compared to supra-physiological doses in supplements). Where functional foods like cherry juice can exert its effect is during the secondary phase, when inflammation and oxidative stress ramp up post-training.

#3 Omega-3

Omega-3 polyunsaturated fats, specifically eicosapentaenoic acid (EPA) and docosahexanoic acid (DHA), are important nutrients that exert anti-inflammatory effects. Omega-3 fats like EPA and DHA are found in highest abundance in cold, deep-water fatty fish (e.g. salmon, mackerel, anchovies, sardines, herring, etc.), seafood (e.g. oysters, mussels, etc.), grass-fed beef and nuts like macadamia and walnuts

Numerous studies have shown beneficial effects of omega-3 on inflammation, oxidative stress, and muscle function after intense exercise.(22,23,24,25)

Interestingly, there appears to be a “loading phase” of approximately two weeks to see changes in muscle omega-3 composition. A recent study found a highly effective loading protocol to be 5g/day dose of fish oil capsules (providing 3,500mg EPA and 900mg DHA), however this is much higher than the current recommendations.(26) Typically, a dose of 1,000-1,500mg (combined EPA/DHA) is suggested in athletes, however more research is needed in this area to confirm an ideal dose.

#4 Vitamin D

Vitamin D isn’t really a vitamin. In truth, it’s a seco-steroid hormone acquired by the body through exposure to the sun (e.g. ultraviolet B radiation or UVB). Sedentary lifestyles in the general population and athletes training indoors (or even outdoors in sun-shy athletes wearing skin covering apparel) has led to a large of number of athletes and active people being diagnose with deficient (< 30 nmol/L 25[OH]D) or insufficient levels of vitamin D. 

In the last decade, new technology has allowed for discoveries of the important effects of vitamin D on muscle function and performance.

Vitamin D is a potent regulator of the immune system and has shown to exert potentially important effects on athletic recovery; anti-inflammatory response post-exercise was found to correlate with the individual’s vitamin D levels, runners with low vitamin D exhibited increase inflammatory responses post-exercise, and athletes performing eccentric-concentric jumps on a plyo-press displayed faster recovery at higher vitamin D status.(27,28)

#5 Creatine

Creatine is keystone supplement in many athlete’s nutritional arsenal. However, many are unaware of the impacts of creatine on recovery. Creatine has shown beneficial effects on satellite cell number and muscle function post-training.(29)

DOWNLOAD THIS INFOGRAPHIC of EVIDENCE-BASED RECOVERY SOLUTIONS to inform your practice below…

DOWNLOAD THIS INFOGRAPHIC of EVIDENCE-BASED RECOVERY SOLUTIONS to inform your practice below…

The Bottom Line

Exercise-induced muscle damage is an important and natural phenomenon that triggers the positive and beneficial adaptations to exercise. In the general population, training stimulus and volume is unlikely to require additional recovery support beyond the nutrition fundamentals of adequate protein, omega-3 and vitamin D intake are likely all you need to support your training goals. 

In athletes, the stakes are much higher. Greater training volume and intensity, as well as two-a-day (sometimes three-a-day training in MMA athletes!) increases the need for the application of functional food strategies to support quicker recovery. 

As always, think about the typetiming, and total amount of the supplement, functional food, or nutritional strategy you’re implementing with clients and athletes.  

(Now get back to your training!)

Dr. Marc Bubbs ND, CISSN, CSCS

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References

1)    Byrne, C., Eston, R. G., & Edwards, R. H. T. (2001). Characteristics of isometric and dynamic strength loss following eccentric exercise-induced muscle damage. Scandinavian Journal of Medicine & Science in Sports, 11(3), 134–140.

2)    Marcora, S. M., & Bosio, A. (2007). Effect of exercise-induced muscle damage on endurance running performance in humans. Scandinavian Journal of Medicine & Science in Sports, 17(6), 662–671. 

3)    Twist, C., & Eston, R. G. (2009). The effect of exercise-induced muscle damage on perceived exertion and cycling endurance performance. European Journal of Applied Physiology, 105(4), 559–567. 

4)    Paschalis, V., Nikolaidis, M. G., Theodorou, A. A., Giakas, G., Jamurtas, A. Z., & Koutedakis, Y. (2010). Eccentric exercise affects the upper limbs more than the lower limbs in position sense and reaction angle. Journal of Sports Sciences,28(1), 33–43. 

5)    Burt, D. G., Lamb, K., Nicholas, C., & Twist, C. (2014). Effects of exercise-induced muscle damage on resting metabolic rate, sub- maximal running and post-exercise oxygen consumption. European Journal of Sport Science,14(4), 337–344. 

6)    Millet, G. Y., Tomazin, K., Verges, S., Vincent, C., Bonnefoy, R., Boisson, R. -C.,...Tarnopolsky, M. (2011). Neuromuscular consequences of an extreme mountain ultra-marathon. PLoS One, 6(2), e17059.

7)    Chen, T. C., Nosaka, K., Lin, M. -J., Chen, H. -L., & Wu, C. -J. (2009). Changes in running economy at different intensities fol- lowing downhill running. Journal of Sports Sciences, 27(11), 1137–1144. 

8)    Leeder, J. D., van Someren, K. A., Gaze, D., Jewell, A., Deshmukh, N. I.K., Shah, I., ... Howatson, G. (2014). Recovery and adaptation from repeated intermittent-sprint exercise. International Journal of Sports Physiology and Performance,9(3), 489–496. 

9)    Child, R. B., Saxton, J. M., & Donnelly, A. E. (1998). Comparison of eccentric knee extensor muscle actions at two muscle lengths on indices of damage and angle-specific force production in humans. Journal of Sports Sciences,16(4), 301–308. 

10)  Nosaka, K., & Sakamoto, K. E. I. (2001). Effect of elbow joint angle on the magnitude of muscle damage to the elbow flexors. Medicine and Science in Sports and Exercise, 33(1), 22–29. 

11)  Chapman, D., Newton, M., Sacco, P., & Nosaka, K. (2006). Greater muscle damage induced by fast versus slow velocity eccentric exercise. International Journal of Sports Medicine,27 (8), 591–598. 

12)  Proske, U., & Morgan, D. L. (2001). Muscle damage from eccentric exercise: Mechanism, mechanical signs, adaptation and clinical applications. The Journal of Physiology,537(Pt 2), 333–345. 

13)  Enoka, R. M. (1996). Eccentric contractions require unique activation strategies by the nervous system. Journal of Applied Physiology (1985), 81(6), 2339–2346.

14)  Ebbeling, C. B., & Clarkson, P. M. (1989). Exercise-induced muscle damage and adaptation. Sports Medicine, 7(4), 207–234. 

15)  Hyldahl, R. D., Olson, T., Welling, T., Groscost, L., & Parcell, A. C. (2014). Satellite cell activity is differentially affected by con- traction mode in human muscle following a work-matched bout of exercise. Frontiers in Physiology,5, 485. 

16)  Phillips, S. M., & Van Loon, L. J. C. (2011). Dietary protein for athletes: From requirements to optimum adaptation. Journal of Sports Sciences,29(Suppl 1), S29–S38. 

17)  Buckley, J. D., Thomson, R. L., Coates, A. M., Howe, P. R. C., DeNichilo, M. O., & Rowney, M. K. (2010). Supplementation with a whey protein hydrolysate enhances recovery of muscle force-generating capacity following eccentric exercise. Journal of Science and Medicine in Sport, 13(1), 178–181. 

18)  Nosaka, K., Sacco, P., & Mawatari, K. (2006). Effects of amino acid supplementation on muscle soreness and damage. International Journal of Sport Nutrition and Exercise Metabolism, 16(6), 620–635. 

19)  Seeram, N. P., Aviram, M., Zhang, Y., Henning, S. M., Feng, L., Dreher, M., & Heber, D. (2008). Comparison of antioxidant potency of commonly consumed polyphenol-rich beverages in the United States. Journal of Agricultural and Food Chemistry, 56(4), 1415–1422. 

20)  Wang, H., Nair, M. G., Strasburg, G. M., Chang, Y. -C., Booren, A. M., Gray, J. I., & DeWitt, D. L. (1999). Antioxidant and anti- inflammatory activities of anthocyanins and their aglycon, cyani- din, from tart cherries. Journal of Natural Products,62(5), 802. 

21)  Connolly, D. A., McHugh, M. P., Padilla-Zakour, O. I., Carlson, L., & Sayers, S. P. (2006). Efficacy of a tart cherry juice blend in preventing the symptoms of muscle damage. British Journal of Sports Medicine, 40(8), 679–683. discussion 683. 

22)  DiLorenzo, F. M., Drager, C. J., & Rankin, J. W. (2014). Docosahexaenoic acid affects markers of inflammation and muscle damage after eccentric exercise. Journal of Strength and Conditioning Research, 28(10), 2768–2774. 

23)  Gray, P., Chappell, A., Jenkinson, A. M., Thies, F., & Gray, S. R. (2014). Fish oil supplementation reduces markers of oxidative stress but not muscle soreness after eccentric exercise. International Journal of Sport Nutrition and Exercise Metabolism, 24(2), 206–214. 

24)  Jouris, K. B., McDaniel, J. L., & Weiss, E. P. (2011). The effect of omega-3 fatty acid supplementation on the inflammatory response to eccentric strength exercise. Journal of Sports Science & Medicine, 10(3), 432–438. 

25)  Phillips, T., Childs, A. C., Dreon, D. M., Phinney, S., & Leeuwenburgh, C. (2003). A dietary supplement attenuates IL-6 and CRP after eccentric exercise in untrained males. Medicine & Science in Sports & Exercise,35(12), 2032–2037. 

26)  McGlory, C., Galloway, S. D. R., Hamilton, D. L., McClintock, C., Breen, L., Dick, J. R., ...Tipton, K. D. (2014). Temporal changes in human skeletal muscle and blood lipid composition with fish oil supplementation. Prostaglandins, Leukotrienes and Essential Fatty Acids (PLEFA), 90(6), 199–206. 

27)  Barker, T., Martins, T. B., Hill, H. R., Kjeldsberg, C. R., Dixon, B. M., Schneider, & E. D. (2014). Vitamin D sufficiency associates with an increase in anti-inflammatory cytokines after intense exercise in humans. Cytokine, 65(2), 134–137. 

28)  Willis, K. S., Smith, D. T., Broughton, K. S., & Larson-Meyer, E. D. (2012). Vitamin D status and biomarkers of in ammation in runners. Open Access Journal of Sports Medicine, 3, 35–42. 

29)  Olsen, S. (2006). Creatine supplementation augments the increase in satellite cell and myonuclei number in human skeletal muscle induced by strength training. Journal of Physiology, 573(Pt 2), 525–534. 

 

 

6 Longevity Tips - Increase Your Health Span

6 Longevity Tips - Increase Your Health Span

Are achy joints simply the inevitable consequence of getting older? How about fatigue or poor sleep? Should you just “learn to live” with a chronic condition or is there something you can do to reverse it? You may have been told by your health practitioner that these symptoms are due to the natural aging process, but there isn't quite true. The different between "life span" versus "health span" is the final decade is typically in pain and discomfort in the former, while the latter is health and vitality right up until the end.  Which option do you prefer?

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What To Do If You Have Seasonal Affective Disorder (SAD)?

What To Do If You Have Seasonal Affective Disorder (SAD)?

It’s that time of year again. The darkest and shortest days of the year don’t just bring about cold weather; they can also bring about significant changes in your mood and how you feel. 

Seasonal affective disorder (SAD) is a real thing that affects over 10 million Americans, with another 10-20 million said to struggle with mild symptoms.

If you live in a city with a true winter climate – like New York, Toronto, or London – you’re up to 10 times more likely to struggle with mild to moderate SAD. Also, adolescents and young adults are more likely to be affected.

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Vitamin D & Endurance Sport Performance

Vitamin D & Endurance Sport Performance

Vitamin D has been gaining significant momentum recently in the research for its ability to influence over 1,000 different genes in the body and subsequently some important performance parameters. Failing to get sufficient vitamin D regularly can negatively impact many endurance parameters, including maximal aerobic capacity (VO2 max), susceptibility to colds and flu, inflammation, recovery, and stress fractures.

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21 Foods To Boost Your Immunity

2017_21 Foods To Boost Immunity.png

The darker, shorter and colder days of winter are upon us and with it comes an increase in colds and flu. The first wave of patients with sore throats and congestion has already passed through my office, so now is a great time to think about how you can support your immune system. There are several key deficiencies that commonly rear their ugly heads over the fall and winter months and contribute to increased frequency and severity of colds and flu. Nothing will slow your productivity at work, in the gym, or family time at home quicker than sick days.

If you are working long hours, exercising intensely, or have kids in daycare or school, then you’ll likely be more exposed to bacteria and viruses that can leave you stuck at home in bed. The research tells us that as your cortisol stress levels increase (from busy days, meeting deadlines, or getting up early with the kids) your first-line of immune defense or innate immune system function decreases.1This leaves your immune defense team short-handed.

Staying active is a great way to enhance your immunity but the more intensely you train (or the greater your training load), the quicker you deplete critical ‘immune soldiers’ called natural killer cells (NK).2 Studies show your immune system can be depressed for 24-72 hours after intense training, which means you need to provide the right support to reduce your risk of colds and flu.3

What can you do to boost your immunity this winter? (The answer is on your dinner plate!)

VITAMIN D

If you live in a northern climate with a true fall and winter season, obtaining the right amount of vitamin D is critical for keeping your immune system firing on all cylinders. Vitamin D deficiency is associated with decreased innate immunity and increased risk for infections.4

The best part of a Food First approach to your nutrition strategy is that it provides you with nutrient-dense food choices. To keep your vitamin D levels from plummeting over the winter months, increase your intake with these five vitamin D containing foods:

  • Cod Liver Oil – 1,400 IU per tbsp. (your grandma knew best!)
  • Cold-Water Fatty Fish – trout (645 IU per 3 ounce), salmon, or mackerel
  • Medicinal Mushrooms – Portobello (375 IU per mushroom) or maitake
  • Pork – 78 IU per 3 oz. serving
  • Eggs – 44IU per egg

The Vitamin D Society recommends maintaining your vitamin D levels between 100-150 (nmol/l), so if you struggle with colds and flu, or low mood over the winter, then getting your levels tested would be beneficial.5

VITAMIN A

If you are low in Vitamin A, it will significantly impair your mucosal immunity and leave you more prone to upper respiratory tract infections (URTI).6 If you work in an office, have kids in daycare or school, or train intensely than you’ll be a much greater risk of URTI, especially through the winter months.

Traditiona diets around the world are loaded with nutrient dense meats that are the richest source of preformed vitamin A. You can also get significant beta-caretene (which converts to vitamin A) from fruits and veggies.

Try these five foods rich vitamin A foods to keep your immune system robust:

  • Turkey and Beef Liver – 17,000 IU and 6,400 IU per 2.6 oz., respectively.
  • Cod Liver Oil – 4,150 IU per tbsp.
  • Sweet potatoes – 1,100 IU per medium size
  • Pumpkin -1,000 IU per ½ cup
  • Carrots – 700 IU per ½ cup

VITAMIN C & ZINC

Vitamin C and zinc is a powerful combo for ramping up your immune army and fighting off bacteria and viruses. Vitamin C improves the response of neutrophils and lymphocytes, important immune cells that are the ‘front-line soldiers’ of your innate immune system.7,8 Zinc is essential for optimal function of your thymus gland, responsible for developing the ‘special forces’ immune cells of your adaptive immune system.9 This is the seek and destroy arm of your immunity, crucial for knocking out foreign invaders once they’ve breached your first-line of defense.

A nutrition strategy rich in animal protein is the best dietary source of zinc, while a mix of fruit and veggies are key for boosting your vitamin C intake (some sources may surprise you!). To ensure you’re meeting your body’s increased demands throughout the fall/winter months, be sure to include the following foods:

Vitamin C

  • Yellow Bell Peppers – 345mg per large pepper
  • Broccoli – 92mg per cup (chopped)
  • Kale – 80mg per cup (chopped)
  • Orange – 70mg per fruit (medium)
  • Kiwis – 64mg per fruit

Zinc

  • Oysters – 33mg per 6 oysters
  • Beef – 14mg per fillet (4.5oz.)
  • Lamb – 7mg per 3oz.
  • Pork – 4.3mg per 3oz.
  • Ginger 

ADD A PROBIOTIC

There is inherent ‘cross-talk’ between your gut and immune system, therefore ensuring the right balance of healthy microbiota in your intestinal tract will go a long way to fighting off colds and flus.10,11 Common fermented foods and Paleo staples like kombucha tea, sauerkraut, and kimchi, are great options for increasing ‘good’ gut bacteria. In addition, the polyphenols found in green tea also promote the growth of beneficial gut bacteria. If you struggle with frequent or persistent colds or flu, you may want to add a probiotic supplement to add further immune support.

Limiting the growth of ‘bad’ or dysbiotic gut bacteria is crucial to maintaining optimal intestinal microflora and therefore immunity. Short-chain saturated fats like butyric acid and lauric acid, found in butter and coconut oil, exert potent antmicrobial effects that help to keep bad bacteria in check.12,13

Don’t let the cold, dark months slow you down. Enhance your diet by incorporating the foods richest in the key immune boosting nutrients – vitamin D, A, C, zinc, and probiotics – to increase your resiliency this cold and flu season.

Enjoy a healthy winter!

Dr. Marc Bubbs ND, CISSN, CSCS

 

Check out the rest of our articles in the IMMUNITY SERIES...

REFERENCES

[1]Nieman DC et al. Influence of carbohydrate on the immune response to intensive, prolonged exercise. Exerc Immunol Rev 1998;4:64-76.

[2] Nieman DC, Pedersen BK. Exercise and immune function. Recent developments. Sports Med 1999;27(2):73-80.

[3] Walsh PH et al. Position statement. Part one: Immune function & exercise. Exerc Immunol Rev.2011;17:6-63.

[4] Youssef D et al. Vitamin D’s potential to reduce the risk of hospital-acquired infections. Dermatoendocrinol. 2012 Apr 1;4(2):167-75

[5] Heaney R, Bggerly C, Sorenson M, Vieth R. Toronto Vitamin D Disease Prevention Symposium. November 6th, 2013. Toronto, ON

[6] Semba RD. The role of vitamin A and related retinoids in immune function. Nutr Rev. 1998;56(1 Pt 2):S38-48

[7] Douglas RM et al. Vitamin C for preventing and treating the common cold. Cochrane Database Systematic Review. 2004 Oct 18;(4):CD000980.

[8] Peters EM, Goetzche JM, Grobbelaar B, Noakes TD. Vitamin C supplementation reduces the incidence of post race symptoms of upper-respiratory-tract infection in ultra marathon runners. Am J Clin Nutr 1993 Feb;57(2):170-4.

[9] Mangini S et al. A combination of high-dose vitamin C plus zinc for the common cold. J Int Med Res. 2012;40(1):28-42.

[10] Rask C et al. Differential effect on cell-mediated immunity in human volunteers after intake of different lactobacilli. Clin Exp Immunol 2013 May;172(2):321-32.

[11] Madden J.A.J. et al. Effect of probiotics on preventing disruption of the intestinal microflora following antibiotic therapy: A double-blind, placebo-controlled pilot study. Int Immunophar 2005: 5: 1091-1097.

[12] Mortesen FV, Nielsen H, Aalkjaer C, et al. Short chain fatty acids relax isolated resistance arteries from the human ileum by a mechanism dependent on anion-exchange. Pharmacol Toxicoli 1994;75(3-4):181-5. 6.

[13] Mortesen FV, Nielsen H, Mulvaney MJ, et al. Short chain fatty acids dilate isolated human colonic reistance arteries. Gut 1990;31(12):1391-4.

The Athletic Potential of Vitamin D

It’s the middle of winter, and the days are dark and cold. But you’re still training intensely and eating clean to get ready for your upcoming competition. Unfortunately, there is one vitamin no amount of clean eating can fix, especially in athletes. New research suggests maintaining the right levels of vitamin D may improve several elements of performance, including your VO2 max, sprint capacity, and power production.

A Growing Research Field

Exercise dramatically increases an athlete’s demand for vitamin D, as your muscle, heart, and vascular tissue all contain key vitamin D receptors. Today, studies show more than 50 percent of athletes are low in vitamin D.1 While the direct cause isn’t clear, it’s most likely a combination of things like inflammatory processes, muscular damage, increased protein synthesis requirements, increased immune activity, lack of sun exposure, race, and genetics.2

A clear vitamin D deficiency occurs at blood levels less than 20ng/mL (< 50 nmol/L), while insufficiency for athletes is generally defined at blood levels between 20-32 ng/mL (50-80 nmol/L). Insufficiency simply means you’re not getting enough to meet the demands of your activity. Intense training is demanding. New research suggests that 40-50ng/mL (100-125 nmol/L) seems to be the “sweet spot” for supporting optimal athletic performance, and experts agree the body needs daily replenishment to meet that requirement.3,4

Achieving your ideal vitamin D intake may upgrade six key areas of performance:

  1. VO2 max
  2. Muscular power production
  3. Testosterone levels
  4. Inflammation
  5. Susceptibility to colds and flu
  6. Mood

Let’s take a closer look at each.

1. VO2 Max

You likely spend a lot of time planning and periodizing your training to maximize your efforts, but did you know that not having enough vitamin D could compromise your maximal oxygen uptake, or VO2 max, a classic marker for assessing aerobic fitness? New research in professional hockey and soccer players found a strong correlation between low vitamin D status and VO2 max. If you’re a weekend warrior, this relationship may be even stronger.

Experts will tell you just because there is an association doesn’t mean that increasing the amount of vitamin D in your diet will improve performance. However, a new study in vitamin D deficient rowers found that 8 weeks of supplementation (6,000IU per day) resulted in more than a 10 percent improvement of VO2 max. For elite athletes, improving performance by 2-3 percent is the difference between a podium finish and being in the middle of the pack.5,6,7 Remember, more is not always better. Talk to your doctor and get tested before supplementing with high doses of vitamin D.

2. Power Production

Your muscle tissues have many key receptor sites for vitamin D, and they seem to play a key role in supporting power production. For athletes, increasing power production translates to improved performance on the playing field. Recently, the Canadian Women’s National Hockey strength and conditioning team found athletes with higher power production were more likely to make the final selection for the national team. 

Additionally, a study in soccer players found increasing baseline vitamin D status over an 8-week period resulted in an increase in 10-meter sprint times and vertical jump.8 While not all studies found this relationship, it’s important to ensure you meet the minimal baseline requirements to ensure maximum training benefit.

3. Testosterone Levels

Low testosterone is a common symptom in athletes who are over-reaching and overtraining. Unfortunately, too many people look for a quick fix rather than address why their testosterone levels are low in the first place. Vitamin D is a precursor to testosterone production and may increase the binding efficiency of testosterone to its receptors.4 Low levels are linked to increased protein breakdown, reduced strength, and increased body fat.

If you’re an athlete over age sixty, the connection is even more compelling because low vitamin D levels at that age correlate strongly to low testosterone levels.9 A new study over a 12-month time span found that adding approximately 3,000 IU of vitamin D daily resulted in increased total, bioavailable, and free testosterone.10 For those training through the winter, low testosterone combined with intense training will lead to sub-optimal recovery and increased risk of symptoms of overtraining (i.e., increased muscle soreness, low mood, fatigue, low libido, etc.). This is especially true for athletes who compete in indoor sports year round that limit sun exposure.

4. Inflammation

Inflammation is a natural product of intense training. However, too much inflammation can impair muscular function and future performance. One study showed adding an extra 4,000 IU of vitamin D daily can offset the increased inflammatory reaction with a high-volume training load of 10 sets of 10 reps of compound exercises in men and women.11

Interestingly, the group adding extra vitamin D also noted a mere 6 percent drop in power output over the course of the workout, while the group not supplementing had a 32 percent decrease in power. Amazingly, this deficit lasted for up to 48 hours. If you’re preparing for a competition or the CrossFit Games, maintaining power output during competition is critical to your performance.

5. Colds and Flu

There is nothing worse than catching a cold or flu in the days leading up to a competition. All those hard training days and dedication to be at the top of your game, only to be cut short by a nasty bug. If you’re low in vitamin D, the “foot soldier” immune cells that make up your innate immune system will also be low. If this first-line of immune defense is compromised, you’ll be at increased risk of infection.12

Vitamin D promotes hundreds of anti-microbial proteins in the body that fight off bacteria and viruses and helps keep your immune system robust in the build-up to competition. Research in athletic populations highlights that maintaining optimal levels of vitamin D can reduce common infectious illnesses.13 If your levels are low, your immunity and performance will likely be compromised.

6. Mood

Training intensely isn’t just tough on your muscles and joints. It also takes a toll on your mental game. If you're an athlete, you regularly push that fine line between over-reaching (pushing beyond your limits to grow stronger) and overtraining (pushing too far beyond your limits). Therefore, it’s crucial to maintain a positive mood as you fight through the toughest weeks of your training.

Low levels of vitamin D are consistently associated with low mood and depression, and because many athletes train indoors through the winter months (and sometimes even summer, depending on your sport), deficient levels can impair you sense of well-being.14 Cognitive decline also impacts your decision-making abilities, which are crucial in the heat of competition, yet fatigue and pain make them very difficult.

Sources of Vitamin D

Now that you know vitamin D is key for optimal performance, where is the best place to get it? The sun is far and away your best source of vitamin D. Fifteen minutes of exposure on 5 percent of your skin leads to 10,000-20,000 IU of vitamin D production.4 If you live in a city with a true winter – north of the 42nd parallel – you’ll need more than sun exposure alone to meet your demands, as the sun isn’t high enough in the sky for an adequate dose.

Including vitamin D rich foods in your diet should always be your foundation, and the best dietary sources include egg yolks, pork (yes, bacon!), mushrooms, fortified milk, and yogurt (if you struggle to digest dairy effectively, discontinue).

Of course, if you live in a city with a true winter climate, food alone won’t meet your demands. The general recommendation for supplementing with vitamin D during winter is 1,000-2,000 IU per day. However, this is the case for the general population, not athletes. The research on athletes suggests between 4,000-6,000 IU of vitamin D3 daily is a good bet, however this should only be taken during your intense training phases (up to 8-12 weeks), or from November to March. If you decide to take vitamin D doses greater than 2,000 IU, you must get regular blood tests done with your doctor.

Give Yourself a Winning Edge

Whether your goal for 2016 is achieving a new personal best or finishing on top of the podium, make sure your vitamin D levels are adequate. Assess your vitamin D status, add more vitamin D-rich foods, and find the right supplement strategy to meet your needs.

Intense training requires a robust nutrition plan to meet your body’s demands, and failing to adequately replenish vitamin D can negatively impact too many key systems to ignore. Get your daily dose of vitamin D this winter. The research shows it can make all the difference.

(Read the rest of my article @BreakingMuscle)

Dr. Marc Bubbs ND, CISSN, CSCS

 

References

1. Farrokhyar F, et al., “Prevalence of vitamin D inadequacy in athletes: A systematic review and meta-analysis,” Sport Medicine 5 (2014): 365–78.

2. Willis KS, Smith DT, Broughton KS, Larson-Meyer DE. “Vitamin D status and biomarkers of inflmmation in runners,” Journal of Sports Medicine, 3 (2012): 35-42.

3. Ogan D, Pritchett K. “Vitamin D and the athlete: Risks, recommendations, and benefits,” Nutrients 5 (2013): 1856–1868.

4. Dahlquist D et al. “Plausible ergogenic effects of vitamin D on athletic performance and recovery,” Journal of the International Society of Sports Nutrition, 12 (2015):33

5. Koundourakis N et al. “Relation of vitamin D level to maximal oxygen uptake in adults,” American Journal of Cardiology, 107 (2011):1246–9.

6. Forney L, et al. “Vitamin D status, body composition, and fitness measures in college-aged students,” Journal of Strength and Conditioning Research, 28 (2014): 814–24.

7. Jastrz?bski Z. “Effect of vitamin D supplementation on the level of physical fitness and blood parameters of rowers during the 8-week high intensity training,” Facicula Educ Fiz ?i Sport, 2 (2014): 57–67.

8. Close G et al. “Assessment of vitamin D concentration in non-supplemented professional athletes and healthy adults during the winter months in the UK: implications for skeletal muscle function,” Journal of Sports Science, 31 (2013): 344–53.

9. Wehr et al. “Association of vitamin D status with serum androgen levels in men,” Clinical Endocrinology (Oxf), 73 (2010): 243–8.

10. Pilz S, et al. “Effect of vitamin D supplementation on testosterone levels in men,” Hormone and Metabolic Research, 43 (2011): 223–5.

11. Barker T et al. "Supplemental vitamin D enhances the recovery in peak isometric force shortly after intense exercise," Nutr Metab (Lond), 10 (2013): 69.

12. Youssef D et al. “Vitamin D’s potential to reduce the risk of hospital-acquired infections,” Dermatoendocrinol, 4(2012):167-75.

13. Larson E. “Vitamin D supplementation in athletes,” Nestle Nutrition Institute Workshop Series, 75 (2013): 109-21.

14. Polak M et al. “Serum 25-hydroxyvitamin D concentrations and depressive symptoms among young adult men and women,” Nutrients, 6 (2014): 4720–30.

Vitamin D and Omega-3 Supplements on The Paleo Diet

Choosing a Paleo diet and eating more in tune with how we’ve evolved provides the body with a robust amount of essential protein, healthy fats, gluten-free carbohydrates and nutrient dense veggies. An ancestral approach to eating also provides your body with key nutrients, vitamins and minerals the way nature intended. Does this mean that supplementation is unnecessary if you’re following a Paleo lifestyle? It’s a complicated question.

Most articles and blogs about supplements inevitably discuss the benefits or drawbacks of multi-vitamins. Research shows that if you eat a diet centered around the most nutrient dense foods – quality meats, veggies and fats – you’ll likely already be achieving a therapeutic dose for most vitamins and minerals. When intake is at a supra-physiological dose (that can never be found in nature), too many vitamins can actually put you at risk of chronic disease. Does this mean if you’re following a Paleo diet you don’t need any supplements?

Let’s look at the two most common instances where supplementation might still be a good idea, vitamin D and omega-3 fats. In both of these cases, although a Paleo diet is a great place to start, for many people this may not be enough.

SHOULD YOU SUPPLEMENT WITH VITAMIN D?

Vitamin D is classically known as an essential nutrient for bone health and immunity, however new research shows this fat-soluble vitamin has much more profound impacts on your health and well-being.

How important is vitamin D? Dr. Michael Holick, physician and vitamin D expert sums it up. “Imagine what would happen if a drug company came out with single pill that reduces the risk of cancer, heart attack, stroke, osteoporosis, PMS, depression and various autoimmune conditions? There would be a media frenzy the likes of which has never been seen before! Such a drug exists… it’s the sun.”1, 2, 3

Vitamin D is different than other vitamins because it’s created under your skin when ultraviolet light from the sun interacts with a specific enzyme to form cholecalciferol or vitamin D3. However, exposure to daily sunlight is no longer the norm as we are cooped up in cubicles all day and the deeply ingrained ancestral benefits of light exposure are overlooked.

It’s estimated that up to 70% of the American population is deficient in vitamin D (defined as blood levels below 20ng/mL or 50 nmol/L), or suffering from vitamin D insufficiency, a level above a diagnosed deficiency but still not sufficient for good health (measured as 20-32 ng/mL or 50-80nmol/L). 4

If you live in a northern climate with a true winter season, or north of the 49th parallel, it’s very difficult to achieve the required blood levels of vitamin D from food alone. While cold-water fatty fish, eggs and mushrooms are good foods sources of vitamin D, in the dead of winter they’re likely not enough. Adding a supplement can be highly beneficial.

The standard medical recommendation for vitamin D drops is 1,000-2,000 IU per day, however in the darkest winter months you may need a higher dose. Remember, always get your blood levels tested and work with a doctor if you’re thinking of supplementing with more than the recommended dose. The normal range is typically between 32-50ng/mL (80-125nmol/L) and for athletes new research suggests achieving levels greater than 40ng/mL (100nmol/L) to support superior performance and recovery.5 Be sure to take your vitamin D supplement with a meal that includes fat for optimal absorption.

SHOULD YOU SUPPLEMENT WITH FISH OILS?

Extra long-chain fats eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are the omega-3 ‘all-stars’ when it comes to supporting overall health and combating chronic disease. While most people know the benefits of omega-3 fats for cardiovascular health, many don’t realize they also help reduce the risk of diabetes and depression, protect against mental stress, and even support athletic performance by improving muscle protein synthesis and controlling excessive inflammation.

How important are omega-3 fats? In 2013, the Cardiovascular Healthy Study found that people with the highest omega-3 (e.g. EPA and DHA) levels in their blood had the lowest overall mortality rates.6 In short, the more omega-3 fats you consume, the less chance you have of dying from absolutely any cause. The good news is they are found in abundance in a Paleo diet (e.g. grass-fed meats, wild ocean fish, farm fresh eggs). However, modern day living and long, busy days might mean you’ll benefit from extra support.

If you’re prone to low mood or depression, or cope with regularly high stress levels fish oils could well be an important key to improving your brain health. A study in the Journal of Clinical Psychiatry found people experiencing depression had consistently lower levels of essential fatty acids in their blood. When subjects supplemented with fish oils they had significant improvements in their Hamilton Rating Scale, a recognized evaluation system for depression.7 The British Journal of Nutrition also discovered that supplementing with fish oils helps reduce the adrenal over-activation associated with high levels of mental stress.8

Rates of diabetes and pre-diabetes have never been higher, and constantly being on the go is just one factor that can lead to snacking on convenience foods that are high in processed carbs and sugars. A recent study of fish oil supplementation effects on blood sugar and insulin levels over a 3-week period found significant improvements in insulin function in those with elevated levels.9

Of course, it’s not enough just to increase your omega-3 intake. It’s far too easy to obtain excessive amounts of omega-6 type fats in today’s world, whether from processed foods, restaurant eating, or convenience snacks. The beauty of adopting a Paleo diet is that it often naturally restores this common imbalance. However, the impacts of modern living may still leave you short.

Unless you’re eating 1-2 pieces of cold, deep-water fatty fish daily, it’s best to add an omega-3 supplement rich in EPA/DHA. Fish oil is the richest in EPA and DHA, however krill oil, sea oil, and sea algae are all viable options as well. Aim to supplement with 1,000-1,500mg of combined EPA and DHA daily.

If you’re an athlete and training intensely fish oil supplementation can be a game changer. Supplementation can lead to an amazing 50% increase in the up-regulation of mTOR, the genetic signaling pathway that stimulates lean muscle growth, leading to significant increases in muscle protein synthesis and muscular hypertrophy.10If you’re serious about your training, adding extra omega-3 fats to your sports nutrition arsenal is important.

A Paleo diet is a great way to cover all your bases on the nutrition front. However, depending on your genetics, where you live, how busy you are, and your lifestyle, diet may not be enough to correct low or insufficient levels of vitamin D and omega-3 fats. Adding these two supplements into your regime, particularly throughout the winter months, may be the fix you need to improve your health, productivity at work and performance in the gym.

(This article originally appeared @ThePaleoDiet.com)

Dr. Marc Bubbs ND, CISSN, CSCS

Want to learn more? Listen to Paleo founder Dr. Loren Cordain PhD in episode #10 of the Dr. Bubbs Performance Podcast.

 

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REFERENCES

  1. Holick M.Vitamin D Deficiency:What A Pain It Is. Mayo Clin Proc 2003 78(12):1457-59Holick, M. Article Review: Vitamin D Deficiency. NEJM Medical Progress. 2007, 357:266-81.
  2. Holick, M. Shinning A Light On Vitamin D-Cancer Connection IARC Report. Dermato-Endocrinology, 2009 1(1):4-6
  3. Hanley D, Davison, K. Symposium: Vitamin D Insufficiency: A significant risk Factor in Chronic Disease and Potential Disease-Specific Biomarkers of Vitamin D Insufficiency: Vitamin D Insufficiency in North America. J Nutr 2005, 135:332-37
  4. Koundourakis, N et al. Vitamin D and Exercise Performance in Professional Soccer Players. Plos One. 2014 Jul 3;9(7):e101659.
  5. Mozaffarian D, Lemaitre RN, King IB, et al. Plasma phospholipid long-chain omega-3 fatty acids and total and cause-specific mortality in older adults. A cohort study. Ann Intern Med 2013; 158:515-525.
  6. Su K, Huang S, Chiu C, Shen W. Omega-3 fatty acids in major depressive disorder. A preliminary double-blind, placebo-controlled trial. Eur Neuropsychopharmacol 2003;13(4):267-271
  7. Delarue J et al. Fish oil attenuates adrenergic overactivity without altering glucose metabolism during an oral glucose load in haemodialysis patients. Br J Nutr. 2008 May;99(5):1041-7.
  8. Delarue J et al. Interaction of fish oil and a glucocorticoid on metabolic responses to an oral glucose load in healthy human subjects. Br J Nutr. 2006 Feb;95(2):267-72.
  9. Smith GI et al. Omega-3 polyunsaturated fatty acids augment the muscle protein anabolic response to hyperinsulinaemia-hyperaminoacidaemia in healthy young and middle-aged men and women. Clin Sci (Lond). 2011 Sep;121(6):267-78.