Sports Nutrition

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Sports Nutrition

In the context of lifestyle medicine

In the course of their practice, integrative healthcare practitioners encounter patients who are on an exercise continuum, a continuum that ranges from sedentary adults with good intentions all the way to elite athletes. The rapid expansion of research under the umbrella term ‘sports nutrition’ is relevant not only to the very small percentage of North Americans who might be considered elite athletes, but may also be of use to more ordinary folks. We argue that central research findings related to nutritional influences on performance can be selectively used as a means to support sedentary adults who may be struggling with initiating and maintaining an exercise program. Low motivation and high perceived exertion, associated with a lowered mental outlook, are primary obstacles to exercise adherence. We hypothesize that the same nutritional variables that assist in athletic success, including the Mediterranean diet, plant-based antioxidants such as astaxanthin, cherries and beetjuice, fish oil, branched chain amino acids, and creatine, may be factors with much more broad public health implications in terms of being able to support lifestyle change among the ordinary North American population.

Introduction

There are volumes of international research attesting to the value of regular exercise in the reduction of chronic disease risk, overall mortality, and improvement in mental outlook (Blumenthal 2011). Whereas much has been written concerning the obesity epidemic and the prevalence of sedentary behavior, there are small signs of hope related to participation in moderate intensity physical activity among Canadians. For example, the latest statistics show a 4% increase in the number of physically active Canadians compared to this number in 2003 (Humphreys 2013), and separate data also reflects an increase in time spent in more intense levels of leisure time physical activity (Gilmour 2007). Participation in structured athletics, particularly among females in academic programs, has seen dramatic growth (Shriver 2013). Trends also suggest that North Americans are now more likely to receive physical activity recommendations from healthcare providers – a 40% increase over the last decade (Barnes 2012). Current medical students are more likely to be physically active than the general population, and a high level (69%) of Canadian medical students perceive exercise counseling to be highly relevant to clinical practice (Holtz 2013). Overall, this signals a beginning of a shift in perception, with both the public and the medical profession recognizing the importance of physical activity, and beginning to implement small lifestyle changes.

None of these encouraging signs, however, should be used to gloss over the staggering realities that despite these changes, only 15% of Canadian adults are meeting current guidelines for physical activity (Colley 2011). The same research suggesting that soon-to-be physicians believe exercise counseling to be important also shows that 86% of these graduating medical students consider themselves to be ill-prepared for such counseling: 70% reported no training on interacting with patients concerning exercise (Holtz 2013). The more salient point is that integrative healthcare practitioners are increasingly being called upon to provide exercise counseling to patients on a wide spectrum with regard to their comfort and familiarity with physical activity. This spectrum includes Canadians showing the beginnings of interest in the initiating a more active lifestyle for preventive health or for disease management, as well as those who are engaged in elite athletic endeavors. In between these extremes is the so-called “weekend warrior,” engaged in irregular patterns of sport participation, and/or those involved in regularly structured athletic programs such are recreational hockey. Part of the valued expertise that integrative healthcare practitioners bring to such encounters with this diverse group of patients is their in-depth knowledge of nutrition as it relates to dietary practices as well as nutritional supplementation.

The Relevance of Nutrition

The lessons learned from recent studies in the realm of nutrition in sports performance may, at first glance, seem to be of little importance, even trivial, when discussing serious and potentially life-threatening conditions, such as depression and obesity. However, investigations aimed at outcomes such as hitting the finish line tape faster, increasing endurance time to fatigue, or pushing just a bit more weight in strength training, ultimately provide nutritional insights with broader potential (Maughan 2011). It is becoming clear that nutrition is a variable relevant to all those who are on the exercise/sport continuum. It has the potential to influence motivation to participate in physical activity; to reduce perception of fatigue, a barrier that often impedes subsequent participation; to influence cognitive readiness for exercise; to enhance the enjoyment of the exercise experience; to enhance recovery for the next bout of physical activity; to minimize the risk of injury; and, genetic endowment and training being equal, to influence performance itself.

Although the term sports nutrition is often associated with having a primary role in support of the muscles (readiness for task, repair, anabolic processes etc.), nutritional influences are also of vital importance for motivation and performance, factors that are centrally regulated through the central nervous system (CNS). In sedentary adults, the motivation to engage in physical activity is low, and the normal post-exercise lift in mood is often not experienced. For example, in those with depression and/or obesity (vs. healthy/normal weight controls), motivation is a primary barrier to physical activity (Searle 2011). Among these patients, despite their awareness of the benefits of exercise, there are lower pleasure ratings reported after exercise, and perceived exertion is much higher while energy levels lower (Ekkekakis 2011), and this in turn impairs intent to participate in future physical activity (Weinstein 2010). On the other hand, a more positive perception of the experience of exercise encourages future participation (Annesi 2005, Kwan 2010). Integrative healthcare practitioners can take advantage of recent discoveries in nutritional sciences as a means to help break the cycle of negative affect and associated higher levels of perceived exertion, both of which contribute to a generalized exercise intolerance.

The Mediterranean Diet Example

Before discussing more reductionist investigations of single nutrients, e.g. branch chain amino acids, vitamins, minerals etc., it may be worthwhile to examine the influence of the broad aspects of diet as they related to mental outlook and performance. The Mediterranean (Med) diet provides what may be a gold standard for general support of physical and mental performance (Sofi 2010, 2008). The basis of what is now referred to as the contemporary Med diet has been in place for some 10,000 years (Berry 2011), and although details are sparse, there is certainly evidence that various dietary protocols were part of the training schemes of ancient athletes in the region (Grivetti 1997). In the modern context, there are clear characteristics of adherence to a Med diet vs. those consuming standard North American fare (Box 1).

The benefits of high adherence to a Med diet have been well described, ranging from protection against cognitive decline to reduction in the risk of metabolic syndrome (Sofi 2013, 2010, 2008). However, its association with positive mental outlook and resiliency against depressive symptoms bears mention. In a 5-year prospective study, greater adherence to the Med diet was associated with a 25-30% reduction in the risk of depressive symptoms (Sánchez-Villegas 2009). Moreover, adherence to the Med diet has also been linked to physical performance (Milaneschi 2011). In a recent study, adherence to the Med diet was linked to better objective performance results (measured via selfselected pace and walking speed over a 20m distance) in community-dwelling older adults (Shahar 2012). A recent intervention trial found that a 10-day Med diet significantly increased vigor, alertness and contentment among participants vs. controls (McMillan 2011). These are precisely the mood changes that would work towards undoing the motivational barriers to exercise. Among the many mechanisms whereby the Med diet can influence mental outlook, however its ability to reduce inflammatory markers is likely key. Intentional elevation of inflammatory cytokines in healthy adults has been shown to causes low-grade anxiety, depressive symptoms and mental fatigue (DellaGioia 2013, Reichenberg 2001), while Med diet interventions are known to reduce systemic markers of inflammation (Richard 2013). The Med diet may in this way psychologically augment the experience of exercise.

Specific Med Diet Elements

Among the specific components of the Med diet, fish intake and carotenoid intake (an accepted marker of fruit and vegetable consumption), have been linked to muscle strength and physical performance (Cesari 2004, Robinson 2008, Semba 2007). Mechanistically, there is evidence, although not unequivocal, that omega-3 fatty acid-rich fish oil can limit red blood cell deformability, muscle damage and overall inflammation associated with exercise (Mickleborough 2013). Furthermore, omega-3 fatty acids, and eicosapentaenoic acid (EPA) specifically, can potentially influence mental outlook in ways conducive to motivation (Hegarty 2013). Carotenoids serve as a marker of fruit and vegetable consumption, and their associated array of plant-based antioxidants; there is evidence to suggest that antioxidants may provide benefit in reducing the perception of effort during exercise. For example, compared to controls, heart rate and perceived exertion were reduced, and general fatigue score was decreased, when overweight adults were given 500mg of vitamin C for four weeks (Huck 2013).

Supplementation with the carotenoid astaxanthin for 90 days has been shown to reduce objective markers of muscle cell damage (serum creatine kinase) in elite soccer players (Djordjevic 2012). In another study, 28 days of astaxanthin supplementation (vs. placebo) has been shown to significantly improve cycling performance time among competitive cyclists (Earnest 2011). Other colorful dietary components, cherries for example, have been shown to be helpful in reducing postexercise pain, markers of muscle cell damage and inflammation, as well as a more rapid restoration of muscle strength (Bowtell 2011, Connolly 2006, Howatson 2010).

In addition to omega-3 fatty acids and antioxidants, the Med diet is also very high in dietary nitrate, a compound found in green leafy vegetables and beetroot that can increase blood flow in support of exercise performance. Close to a dozen studies using beetroot juice, nitrate-depleted beetroot juice and/or supplemental nitrate (Lidder 2013) have shown that dietary nitrate can improve exercise performance by increasing the efficiency of oxygen utilization (O2 cost is reduced) and increasing ATP synthesis. Among athletes and recreationally fit adults, beetroot significantly increases time to exhaustion (15%), enhances running velocity and reduces perceived exertion over longdistance running, and improves performance in team-sport exercise (Lansley 2011, Murphy 2012, Wylie 2013). One cup of beetjuice contains 5.5 mmol of nitrate, the equivalent of about 350mg; studies have used supplemental dosage forms containing up to 1500mg nitrate in healthy volunteers (Kapil 2010). These findings, showing more efficient metabolic pathways and lowered perceived exertion in particular, clearly suggest potential benefit in those sedentary adults/children who might contemplate initiating an exercise protocol. Of course, leafy green vegetables also carry significant levels of magnesium (Mg) per serving. Mg plays an important role in enzymatic support of muscular function, and even mild deficiency may compromise muscle performance (Matias 2010). Among athletes, dietary Mg intake is positively associated with various isokinetic strength variables and jumping performance tests, independent of total energy intake (Santos 2011). Mg intake is notoriously low in the general population, and this includes athletes and those with depressive disorders (Santos 2011, Yary 2013). Indeed, low Mg levels have been associated with depressive symptoms, chronic fatigue, and muscular pain. Mg is a versatile nutrient, supporting both muscle and mood; it is one that can help mitigate inflammation and oxidative stress, as well as support normal neurotransmitter functioning (Barbagallo 2009). Again, the relevance of Mg on the continuum, from those struggling to break a sedentary lifestyle to those in which sports performance is part of their identity, seems obvious.

General Considerations – Protein, Carbohydrate, Hydration

Scientific investigations in the realm of sports nutrition, particularly related to performance outcomes, have made it increasingly clear that a needs-based, individualized approach is most appropriate (Maughan 2011). That said, there are general nutritional considerations in supporting the process of exercise adaptation. All forms of exercise increase the rate of protein oxidation relative to the resting state; this translates into an increase in dietary protein demands (Phillips 2012). Of course, increased protein does not imply excess protein – 20 to 25 grams of high-quality mixed protein, or 6g of essential amino acids, consumed before or soon after exercise, is typically more than adequate to support remodeling and adaptive processes in muscle tissue subsequent to exercise (Maughan 2012). Branch chain amino acids (BCAA) have an anabolic effect on human muscle tissue (Borgenvik 2012), and supplemented alone or together with taurine, the BCAAs have been shown to reduce post-exercise muscle soreness (Howatson 2012, Ra 2013). Although not a protein, creatine is a significant nitrogen source, and one that can have value in preventing muscular fatigue (Rawson 2011) and loss of skill under conditions of sleep deprivation at relatively small (2-5g) doses (Cook 2011, Rawson 2011). In keeping with our contention that what is good for the athlete may be good for the sedentary adult seeking motivation, consider that 5g creatine per day has been recently shown to augment the effectiveness of antidepressant medications (Lyoo 2012).

Carbohydrate provides critical fuel for the initiation and maintenance of physical activity, training and/or competition. At lower intensity exercise, the body can take advantage of fat oxidation, however, with increasing intensity (particularly endurance exercise) the demand for carbohydrate utilization grows. Endurance exercise in the fasted state is generally not well tolerated in humans (Maughan 2010), and the increase in perceived effort in those without adequate carbohydrate reserves (glycogen) would certainly not encourage adherence to exercise as medicine (Maughan 2012). For post-exercise recovery efforts, although the science is incomplete, the preponderance of evidence suggests that a 2:1 ratio of carbohydrate to protein supplementation is helpful to restore glycogen reserves (Spaccarotella 2011).

The maintenance of proper hydration is yet another top line consideration in sports nutrition. Progressive loss of water and electrolytes as a result of increasing exercise intensity and duration is itself a cause of fatigue. The initiation of exercise in a dehydrated state has been shown to compromise performance in endurance (Goulet 2012). Again, the cognitive angle of even the mildest forms of dehydration cannot be overlooked. Recent studies in schoolchildren and adults have shown diminished cognitive performance in association with mild dehydration, and cognitive restoration produced by correction to a normal hydrated state (Edmonds 2013, Fadda 2012). Perceived exertion is higher among athletes in states of relatively modest hypohydration (Barr 1999), therefore this is likely to be compounded among those who are sedentary. Maintenance of normal hydration (sodium, potassium, magnesium and calcium) before, during, and after physical activity may go a long way toward encouraging adherence to an exercise program.

Conclusion

Studies derived from the burgeoning area of sports nutrition are not simply of relevance to the very small percentage of North Americans who might be considered elite athletes. IHPs can take advantage of sports nutrition research as a means to support a wide variety of patients/clients, perhaps most importantly those sedentary adults who are struggling with the difficult task of initiating and maintaining an exercise program. Low motivation and high perceived exertion, associated with a lowered mental outlook, are primary obstacles to exercise adherence – the same nutritional variables that might allow an athlete to collect a medal or push an extra rep on a weight bar, are the very factors that might have broad public health implications.

References:

Annesi JJ. Relations of self-motivation, perceived physical condition, and exercise-induced changes in revitalization and exhaustion with attendance in women initiating a moderate cardiovascular exercise regimen. Women Health. 2006;42(3):77-93.

Azzini E, Polito A, Fumagalli A, Intorre F, Venneria E, Durazzo A, Zaccaria M, Ciarapica D, Foddai MS, Mauro B, Raguzzini A, Palomba L, Maiani G. Mediterranean Diet Effect: an Italian picture. Nutr J. 2011;10:125.

Barbagallo M, Belvedere M, Dominguez LJ. Magnesium homeostasis and aging. Magnes Res 2009;22(4):235-46.

Barnes PM, Schoenborn CA. Trends in adults receiving a recommendation for exercise or other physical activity from a physician or other health professional. NCHS Data Brief 2012;(86):1-8.

Barr SI. Effects of dehydration on exercise performance. Can J Appl Physiol 1999;24(2):164-72.

Berry EM, Arnoni Y, Aviram M. The Middle Eastern and biblical origins of the Mediterranean diet. Public Health Nutr. 2011;14(12A):2288-95.

Blumenthal JA. New frontiers in cardiovascular behavioral medicine: comparative effectiveness of exercise and medication in treating depression. Cleve Clin J Med 2011;78 Suppl 1:S35-43.

Borgenvik M, Apró W, Blomstrand E. Intake of branchedchain amino acids influences the levels of MAFbx mRNA and MuRF-1 total protein in resting and exercising human muscle. Am J Physiol Endocrinol Metab 2012;302(5):E510-21.

Bowtell JL, Sumners DP, Dyer A, Fox P, Mileva KN. Montmorency cherry juice reduces muscle damage caused by intensive strength exercise. Med Sci Sports Exerc 2011;43(8):1544-51.

Cesari M, Pahor M, Bartali B, Cherubini A, Penninx BW, Williams GR, Atkinson H, Martin A, Guralnik JM, Ferrucci L. Antioxidants and physical performance in elderly persons: the Invecchiare in Chianti (InCHIANTI) study. Am J Clin Nutr 2004;79(2):289-94.

Colley RC, Garriguet D, Janssen I, Craig CL, Clarke J, Tremblay MS. Physical activity of Canadian adults: accelerometer results from the 2007 to 2009 Canadian Health Measures Survey. Health Rep 2011;22(1):7-14.

Connolly DA, McHugh MP, Padilla-Zakour OI, Carlson L, Sayers SP. Efficacy of a tart cherry juice blend in preventing the symptoms of muscle damage. Br J Sports Med. 2006;40(8):679-83;

discussion 683. Cook CJ, Crewther BT, Kilduff LP, Drawer S, Gaviglio CM. Skill execution and sleep deprivation: effects of acute caffeine or creatine supplementation – a randomized placebo-controlled trial. J Int Soc Sports Nutr 2011;8:2.

DellaGioia N, Devine L, Pittman B, Hannestad J. Bupropion pre-treatment of endotoxin-induced depressive symptoms. Brain Behav Immun 2012 Oct 12. [Epub ahead of print]

Djordjevic B, Baralic I, Kotur-Stevuljevic J, Stefanovic A, Ivanisevic J, Radivojevic N, Andjelkovic M, Dikic N. Effect of astaxanthin supplementation on muscle damage and oxidative stress markers in elite young soccer players. Sports Med Phys Fitness 2012;52(4):382-92.

Earnest CP, Lupo M, White KM, Church TS. Effect of astaxanthin on cycling time trial performance. Int J Sports Med 2011;32(11):882-8.

Edmonds CJ, Crombie R, Ballieux H, Gardner MR, Dawkins L. Water consumption, not expectancies about water consumption, affects cognitive performance in adults. Appetite 2013;60(1):148-53.

Ekkekakis P, Parfitt G, Petruzzello SJ. The pleasure and displeasure people feel when they exercise at different intensities: decennial update and progress towards a tripartite rationale for exercise intensity prescription. Sports Med. 2011;41(8):641-71.

Fadda R, Rapinett G, Grathwohl D, Parisi M, Fanari R, Calò CM, Schmitt J. Effects of drinking supplementary water at school on cognitive performance in children. Appetite 2012;59(3):730-7.

Gilmour H. Physically active Canadians. Health Rep 2007;18(3):45-65.

Goulet ED. Dehydration and endurance performance in competitive athletes. Nutr Rev 2012;70 Suppl 2:S132-6.

Grivetti LE, Applegate EA. From Olympia to Atlanta: a cultural-historical perspective on diet and athletic training. J Nutr. 1997;127(5 Suppl):860S-868S.

Hegarty B, Parker G. Fish oil as a management component for mood disorders – an evolving signal. Curr Opin Psychiatry 2013;26(1):33-40.

Holtz KA, Kokotilo KJ, Fitzgerald BE, Frank E. Exercise behaviour and attitudes among fourth-year medical students at the University of British Columbia. Can Fam Physician 2013;59(1):e26-32.

Howatson G, Hoad M, Goodall S, Tallent J, Bell PG, French DN. Exercise-induced muscle damage is reduced in resistancetrained males by branched chain amino acids: a randomized, double-blind, placebo controlled study. J Int Soc Sports Nutr 2012;9(1):20.

Howatson G, McHugh MP, Hill JA, Brouner J, Jewell AP, van Someren KA, Shave RE, Howatson SA. Influence of tart cherry juice on indices of recovery following marathon running. Scand J Med Sci Sports. 2010;20(6):843-52.

Huck CJ, Johnston CS, Beezhold BL, Swan PD. Vitamin C status and perception of effort during exercise in obese adults adhering to a calorie-reduced diet. Nutrition 2013;29(1):42-5.

Humphreys BR, McLeod L, Ruseski JE. Physical activity and health outcomes: evidence from Canada. Health Econ. 2013 Jan 31. [Epub ahead of print]

Kapil V, Milsom AB, Okorie M, Maleki-Toyserkani S, Akram F, Rehman F, Arghandawi S, Pearl V, Benjamin N, Loukogeorgakis S, Macallister R, Hobbs AJ, Webb AJ, Ahluwalia A. Inorganic nitrate supplementation lowers blood pressure in humans: role for nitrite-derived NO. Hypertension. 2010;56(2):274-81.

Kwan BM, Bryan A. In-task and post-task affective response to exercise: translating exercise intentions into behaviour. Br J Health Psychol 2010;15(Pt 1):115-31.

Lansley KE, Winyard PG, Fulford J, Vanhatalo A, Bailey SJ, Blackwell JR, DiMenna FJ, Gilchrist M, Benjamin N, Jones AM. Dietary nitrate supplementation reduces the O2 cost of walking and running: a placebo-controlled study. J Appl Physiol 2011;110(3):591-600.

Lidder S, Webb AJ. Vascular effects of dietary nitrate (as found in green leafy vegetables and beetroot) via the nitrate-nitritenitric oxide pathway. Br J Clin Pharmacol. 2013;75(3):677- 96.

Lyoo IK, Yoon S, Kim TS, Hwang J, Kim JE, Won W, Bae S, Renshaw PF. A randomized, double-blind placebocontrolled trial of oral creatine monohydrate augmentation for enhanced response to a selective serotonin reuptake inhibitor in women with major depressive disorder. Am J Psychiatry 2012;169(9):937-45.

Matias CN, Santos DA, Monteiro CP, Silva AM, Raposo Mde F, Martins F, Sardinha LB, Bicho M, Laires MJ. Magnesium and strength in elite judo athletes according to intracellular water changes. Magnes Res 2010;23(3):138-41.

Maughan RJ, Fallah J, Coyle EF. The effects of fasting on metabolism and performance. Br J Sports Med 2010;44(7):490-4.

Maughan RJ, Burke LM. Practical nutritional recommendations for the athlete. Nestle Nutr Inst Workshop Ser 2011;69:131-49.

Maughan RJ, Shirreffs SM. Nutrition for sports performance: issues and opportunities. Proc Nutr Soc 2012;71(1):112-9.

McMillan L, Owen L, Kras M, Scholey A. Behavioural effects of a 10-day Mediterranean diet. Results from a pilot study evaluating mood and cognitive performance. Appetite 2011;56(1):143-7.

Mickleborough TD. Omega-3 polyunsaturated Fatty acids in physical performance optimization. Int J Sport Nutr Exerc Metab 2013;23(1):83-96.

Milaneschi Y, Bandinelli S, Corsi AM, Lauretani F, Paolisso G, Dominguez LJ, Semba RD, Tanaka T, Abbatecola AM, Talegawkar SA, Guralnik JM, Ferrucci L. Mediterranean diet and mobility decline in older persons. Exp Gerontol 2011;46(4):303-8.

Murphy M, Eliot K, Heuertz RM, Weiss E. Whole beetroot consumption acutely improves running performance. J Acad Nutr Diet 2012;112(4):548-52.

Phillips SM. Dietary protein requirements and adaptive advantages in athletes. Br J Nutr 2012;108 Suppl 2:S158-67.

Ra SG, Miyazaki T, Ishikura K, Nagayama H, Suzuki T, Maeda S, Ito M, Matsuzaki Y, Ohmori H. Additional Effects of Taurine on the Benefits of BCAA Intake for the Delayed-Onset Muscle Soreness and Muscle Damage Induced by High-Intensity Eccentric Exercise. Adv Exp Med Biol 2013;776:179-87.

Rawson ES, Stec MJ, Frederickson SJ, Miles MP. Lowdose creatine supplementation enhances fatigue resistance in the absence of weight gain. Nutrition 2011;27(4):451-5.

Reichenberg A, Yirmiya R, Schuld A, Kraus T, Haack M, Morag A, Pollmächer T. Cytokine-associated emotional and cognitive disturbances in humans. Arch Gen Psychiatry 2001;58(5):445-52.

Richard C, Couture P, Desroches S, Lamarche B. Effect of the Mediterranean diet with and without weight loss on markers of inflammation in men with metabolic syndrome. Obesity 2013;21(1):51-7.

Robinson SM, Jameson KA, Batelaan SF, Martin HJ, Syddall HE, Dennison EM, Cooper C, Sayer AA. Diet and its relationship with grip strength in communitydwelling older men and women: the Hertfordshire cohort study. J Am Geriatr Soc 2008;56(1):84-90.

Sánchez-Villegas A, Delgado-Rodríguez M, Alonso A, Schlatter J, Lahortiga F, Serra Majem L, Martínez- González MA. Association of the Mediterranean dietary pattern with the incidence of depression: the Seguimiento Universidad de Navarra/University of Navarra follow-up (SUN) cohort. Arch Gen Psychiatry. 2009;66(10):1090-8.

Santos DA, Matias CN, Monteiro CP, Silva AM, Rocha PM, Minderico CS, Bettencourt Sardinha L, Laires MJ. Magnesium intake is associated with strength performance in elite basketball, handball and volleyball players. Magnes Res 2011;24(4):215-9.

Searle A, Calnan M, Lewis G, Campbell J, Taylor A, Turner K. Patients’ views of physical activity as treatment for depression: a qualitative study. Br J Gen Pract. 2011;61(585):149-56.

Semba RD, Varadhan R, Bartali B, Ferrucci L, Ricks MO, Blaum C, Fried LP. Low serum carotenoids and development of severe walking disability among older women living in the community: the women’s health and aging study I. Age Ageing 2007;36(1):62-7.

Shahar DR, Houston DK, Hue TF, Lee JS, Sahyoun NR, Tylavsky FA, Geva D, Vardi H, Harris TB. Adherence to mediterranean diet and decline in walking speed over 8 years in community-dwelling older adults. J Am Geriatr Soc 2012;60(10):1881-8.

Shriver LH, Betts NM, Wollenberg G. Dietary intakes and eating habits of college athletes: are female college athletes following the current sports nutrition standards? J Am Coll Health 2013;61(1):10-6.

Sofi F, Macchi C, Abbate R, Gensini GF, Casini A. Mediterranean diet and health. Biofactors. 2013 Mar 29. [Epub ahead of print]

Sofi F, Abbate R, Gensini GF, Casini A. Accruing evidence on benefits of adherence to the Mediterranean diet on health: an updated systematic review and metaanalysis. Am J Clin Nutr. 2010;92(5):1189-96.

Sofi F, Cesari F, Abbate R, Gensini GF, Casini A. Adherence to Mediterranean diet and health status: metaanalysis. BMJ. 2008;337:a1344.

Spaccarotella KJ, Andzel WD. Building a beverage for recovery from endurance activity: a review. J Strength Cond Res 2011;25(11):3198-20.

Weinstein AA, Deuster PA, Francis JL, Beadling C, Kop WJ. The role of depression in short-term mood and fatigue responses to acute exercise. Int J Behav Med 2010;17(1):51-7.

Wylie LJ, Mohr M, Krustrup P, Jackman SR, Ermιdis G, Kelly J, Black MI, Bailey SJ, Vanhatalo A, Jones AM. Dietary nitrate supplementation improves team sportspecific intense intermittent exercise performance. Eur J Appl Physiol. 2013 Feb 1. [Epub ahead of print]

Yary T, Aazami S, Soleimannejad K. Dietary intake of magnesium may modulate depression. Biol Trace Elem Res 2013;151(3):324-9.

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