Caffeine to improve athletic performance

June 27, 2023June 22, 2023 by amystephens

Caffeine to improve athletic performance

Studies have shown an improvement in sports performance when caffeine is consumed before exercise (Clarke, 2018). Here are details about how caffeine works and the safe and effective dose that yields the best results.

How it works:

Caffeine blocks adenosine receptors that, in turn, prevent you from feeling tired. By blocking adenosine receptors, you can feel less pain, increase neuro-excitability, and improve your ability to focus which can lead to ergogenic effects on exercise performance.

Benefits:

Reduces perception of pain and fatigue
Mobilizes fat to use for energy, sparing glycogen
Increasing alertness (reaction time and mood)

Risks:

Effects of too much caffeine can cause jitteriness, shakiness, upset stomach, or reflux. None of these symptoms are ideal before or during a race. Be sure to test out caffeine dose and response before race day.

Dose:

The effective dose of caffeine is 3-6 mg/kg about one hour before competition which is approximately 200-400 mg for a person weighing 150 pounds (70kg) which is equivalent to a tall coffee from Starbucks.

There is a bigger performance benefit when caffeine is reduced prior to competition (Beaumont).

Form:

The amount of caffeine in energy bars, gels and medications tends to be standardized, while the amount in coffee and tea can vary considerably. Be sure to read labels and know how much you are consuming.

Some energy drinks or pre-workout beverages might have caffeine listed as one of these ingredients:

Green tea extract

Guarana

Guayaki yerba mate

Guayusa

Cola nut

Cacao

College athletes:

Caffeine is a banned substance by the NCAA. A urinary caffeine concentration exceeding 15 micrograms per milliliter (corresponding to ingesting about 500 milligrams, the equivalent of six to eight cups of brewed coffee, two to three hours before competition) results in a positive drug test.

* Caffeine content varies among brewing methods. See chart below.

Olympic level athletes:

Caffeine is permitted in sports governed by the World Anti-Doping Agency (WADA).

Food-first approach:

The perception of having increased energy from caffeine will not replace the actual energy provided from food. Successful athletic performance is dependent on a nutrition plan that meets your energy and nutrient needs through food first. Caffeine can be used to improve performance and will be most effective if energy needs are met with food-first.

References

Beaumont R, Cordery P, Funnell M, Mears S, James L, Watson P. Chronic ingestion of a low dose of caffeine induces tolerance to the performance benefits of caffeine. J Sports Sci. 2017 Oct;35(19):1920-1927. doi: 10.1080/02640414.2016.1241421. Epub 2016 Oct 20.

Clarke ND, Richardson DL, Thie J, Taylor R. Coffee Ingestion Enhances 1-Mile Running Race Performance. International Journal Sports Physiology and Performance. 2018;13(6):789-794.

Davis JK, Green JM. Caffeine and anaerobic performance: ergogenic value and mechanisms of action. Sports Med. 2009;39:813–832.

Laurent D, Schneider KE, Prusaczyk WK, et al. Effects of caffeine on muscle glycogen utilization and the neuroendocrine axis during exercise. J Clin Endocrinol Metab. 2000;85:2170–2175.

McLellan TM, Bell DG. The impact of prior coffee consumption on the subsequent ergogenic effect of anhydrous caffeine. Int J Sports Nutr Exerc Metab. 2004;14:698–708.

Spriet LL. Exercise and sport performance with low doses of caffeine. Sports Med. 2014;44:175–184.

Talanian JL, Spriet LL. Low and moderate doses of caffeine late in exercise improve performance in trained cyclists. Appl Physiol Nutr Metab. 2016 Aug;41(8):850-5.

Wiles JD, Bird SR, Hopkins J, Riley M. Effect of caffeinated coffee on running speed, respiratory factors, blood lactate and perceived exertion during 1500-m treadmill running. Br J Sports Med. 1992; 26:116–120.

Eating Disorders in Athletes: Impact on Performance

June 22, 2023October 25, 2022 by amystephens

Eating Disorders in Athletes: Impact on Performance

Eating disorders affect an athlete both mentally and physically and have significant impacts on performance. This blog will discuss the prevalence of eating disorders, identify warning signs in athletes, distinguish the differences and similarities to relative energy deficiency syndrome (REDS), and provide resources for those struggling to seek help. Eating Disorders are a serious issue for everyone, but especially for athletes. Nutrition requirements are high and the inability to fuel an athlete’s body will lead to worsening of disordered eating, injuries, and overall decline in performance.

The most common forms of eating disorders are anorexia, bulimia and binge eating disorder. Anorexia refers to restriction of food and refusal to meet nutritional needs, typically resulting in extreme weight loss. Bulimia is defined by consuming a large quantity of food in a short period of time, followed by a desire to “get rid” of the food through vomiting, exercise, or medications. Often, athletes can have a combination of both. Binge eating disorder is another type of eating disorder characterized by consuming a large quantity of calories in a short period of time. In one study, up to 84% of athletes were found to have subclinical disordered eating, and engaging in maladaptive eating and weight control behaviors, such as binge eating, excessive exercise, strict dieting, fasting, self-induced vomiting, and the use of weight loss supplements (Chatterton, Clifford). Evaluation by a physician or therapist can determine the severity and best form of treatment.

Eating disorders do not discriminate as they affect all races, genders, and socioeconomic classes. Some populations have higher rates of eating disorders. Eating disorders are most commonly screened and diagnosed between the ages 12-19, but can occur at any age. The earlier an athlete is diagnosed, the more likely they are to recover and reverse any damage to their bodies. The longer an eating disorder behavior is untreated, the more difficult the treatment and full recovery become.

Prevalence

13.5% of athletes struggle with an eating disorder (Ghoch).
Up to 45% of female athletes and 19% of male athletes struggle with an eating disorder (Bratland-Sanda)
In a study by Petrie, 19.2% of athletes surveyed had maladaptive eating behaviors such as restricting food intake, limiting food choices, excluding large groups of foods, and purging behavior.

Risk factors for developing eating disorders in athletes

Certain sports that are weight dependent and focus on leanness pose a bigger risk for eating disorders. Both male and female athletes are at risk.

In addition, athletes who have recently undergone stressful events such as an injury are at a greater risk for developing an eating disorder. Athletes who have been struggling with poor performance might want to restrict food and blame the body.

There are additional societal contributions that can lead to eating disorders. It’s important to be aware of these factors so proper education for athletes and coaching staff can help prevent disordered eating among athletes.

Societal contributions include:

A fixation on thinness and the need to have a certain appearance in order to be happy or successful
Social media’s tendency to reinforce negative body image by giving attention to overly thin athletes
Restrictive diet plans promoted by ill-trained professionals
Society’s fixation on toxic positivity and the need to seek perfectionism to achieve one’s goals

All of these practices promote unhealthy relationships with the body and eating patterns. Athletes are no exception. Weight dependent sports not only encourage unhealthy dietary practices, but reward them. The thinner athletes promote themselves as having reached their performance levels due to their thin body type. Misinformation from friends, coaches, and media can cause an athlete to try and achieve an inappropriate level of thinness that causes physical and mental harm to their body. Eating disorders are often overlooked if the athlete is performing well.

Difference between eating disorders and Relative Energy Deficiency Syndrome (RED-S)

Relative Energy Deficiency Syndrome (REDS) is a new classification of symptoms identified in 2014 by International Olympic Committee Mountjoy. REDS is characterized by low calorie intake in relation to energy exerted during exercise. REDS was formerly named “The Female Athlete Triad Syndrome because it affected three key systems in the female body:low calorie intake, menstrual irregularities, and lowered bone density. The term REDS is new but the condition has been in existence for a long time. Simply put, exercising too much and not eating enough causes an imbalance in which the body cannot function at optimal levels. What’s most interesting to me is that someone with REDS can be any body weight. The difference between REDS and an ED is that REDS is an unintentional mismatch of calories. Once an athlete with REDS is evaluated and educated about an appropriate amount of calories to sustain daily exercise and body functions, the deficit is corrected and the body can function properly. ED is further explored if the athlete is unable to willingly consume calories to support energy expenditure.

Sometimes it may not be obvious or easy to diagnose REDS or eating disorders. Someone can be a normal weight but is exercising too much and refueling inadequately. In this instance, athletes may feel that they are eating well, but in truth, are not eating enough calories to support exercise.

Signs of chronic underfueling that warrant further screening to determine if disordered eating is present

Females – change in menstrual cycle, can be longer or lighter periods, it is NOT normal for a female athlete to miss a period
Males – low testosterone and growth hormone. Both are natural performance enhancing hormones made by the body. Low levels can negatively affect sport performances, muscle growth, and energy production. Also important for serotonin uptake for the brain, it can lift mood. (Skolnick)
Hormonal changes can lead to stress fractures and ultimately osteoporosis
Frequent injuries to bones and soft tissues
Isolated, eats alone
Withdrawn behavior
Sudden changes with diet or food choices
Noticeable fluctuations in weight, both up and down
Irritability
Lethargy, difficulty finishing a workout
Digestive issues such as bloating (often mistaken for IBS), gas, diarrhea (this is often worsened by further restricting suspected nutrients)
Decrease in sports performance
Difficulty sleeping
Not seeing improvements in performance despite increasing workouts
Depressed immune system
Decreased cognitive functioning (lower blood sugar supplied to brain)

Treatment

Treatment often begins with an evaluation by a physician, eating disorder dietitian, and therapist. Once the patient is evaluated, they are recommended to the best form of treatment depending on their situation. The dietitian will create a plan that provides adequate calories to support daily expenditure. It can be challenging to find the right physician to help especially since there are differing opinions among professionals. In my experience, missing a period leads to complications related to menstrual cycle and bone growth. It is important to let your doctor know if you’ve lost your period for more than three months as this can be related to underfueling or the result of underlying medical conditions. Your doctor can help guide you to the best treatment approach.

Resources for help

There are many resources to help. If you or someone you are close to might have an eating disorder, here are some important resources that can help:

- Visit your doctor and explain why you are concerned. Be sure to ask if your doctor works with eating disorders.
- For college athletes, visit your health center and explain why you are concerned. The health professionals can conduct proper screenings and assessments.
- Seek out a sports dietitian (ask if they have experience with eating disorders)
- See a school psychologist
- If you think you have an eating disorder, speak to a trusted family member or friend and share your concerns. Eating disorders are isolating so speaking out is a step in the right direction.
- Seek out supportive teammates and coaches and share your eating concerns. They can help you locate the best resources for an evaluation and assessment.
- National Eating Disorders Hotline (NEDA) 1-800-931-2237

References

Bratland-Sanda S, Sundgot-Borgen J. (2013). Eating disorders in athletes: overview of prevalence, risk factors and recommendations for prevention and treatment. Eur J Sport Sci, 13(5):499-508.

Chatterton, J. M., & Petrie, T. A. (2013). Prevalence of disordered eating and pathogenic weight control behaviors among male collegiate athletes. Eating Disorders, 21(4), 328-341.

Clifford, T., & Blyth, C. (2018). A pilot study comparing the prevalence of orthorexia nervosa in regular students and those in university sports teams. Eating and Weight Disorders – Studies on Anorexia, Bulimia and Obesity, 24(3), 473-480.

Conviser, J. H., Schlitzer Tierney, A., Nickols, R. (2018). Essential for best practice: treatment approaches for athletes with eating disorders. J of Clin Sports Psych, 12.

Ghoch, M. E., et al. (2013). Eating disorders, physical fitness, and sport performance: a systematic review. Nutrients, 5:12.

Mehler, P.S., Sabel, A.L., Watson, T. and Andersen, A.E. (2018). High risk of osteoporosis in male patients with eating disorders. Int. J. Eat. Disord, 41: 666-672.

Mountjoy M, Sundgot-Borgen JK, Burke LM, et al. (2018). OC consensus statement on relative energy deficiency in sport (RED-S): 2018 update. Brit J of Sports Med, 52:687-697.

Petrie, Trent, Greenleaf, Christy, Reel, Justine, Carter, Jennifer. (2018). Prevalence of Eating Disorders and Disordered Eating Behaviors Among Male Collegiate Athletes. Psych of Men & Masculinity, 9: 267-277.

Scott CL, Plateau CR, Haycraft E. (2020). Teammate influences, psychological well-being, and athletes’ eating and exercise psychopathology: A moderated mediation analysis. Int J Eat Disord, 53(4):564-573.

Shufelt CL, Torbati T, Dutra E. (2017). Hypothalamic Amenorrhea and the Long-Term Health Consequences. Semin Reprod Med, 35(3):256-262.

Skolnick A, Schulman RC, Galindo RJ, Mechanick JI. (2016). The endocrinopathies of male anorexia nervosa: case series. AACE Clin Case Rep, 2(4):e351-e357.

Feature: How to Eat Before Sports Tryouts, According to a Dietitian

June 26, 2023October 4, 2022 by amystephens

FEATURE: How to Eat Before Sports Tryouts, According to a Dietitian

Amy’s recommendations on Foods to eat before sports tryouts featured on Livestrong.

Hydrating in heat and humidity

June 23, 2023August 19, 2021 by amystephens

Hydrating in heat and humidity

Water is the forgotten nutrient

Exercise produces heat and leaves the body as sweat to stay cool. Studies have repeatedly shown that losing more than 2% body weight impacts performance (James). More sweat is produced when the temperatures are higher or when humidity is high. Dehydration results in an increase in one’s core temperature, reduced cardiovascular function and imparied exercise performance.

Essentially, dehydration increases an athlete’s perceived effort and reduces the ability to continue exercising at a high level (Nybo). If you’re overheating, the body will prioritize cooling itself versus rapid energy production (James).

Role of sweat

During exercise, the body produces heat and energy. Sweat is the body’s built-in cooling system that enables the body to make more energy. In warmer temperatures, exercise raises core temperatures at a faster rate which require more water expelled through the skin to keep the body cool. As temperatures increase, our bodies respond by sweating more. However, humidity compounds this problem by preventing evaporation. In situations where humidity levels are high, as we experience on the east coast all summer long, there is more moisture in the air and the sweat does not evaporate. As a result, the body’s core temperature increases, making exercise seem harder.

Dehydration affects performance

Many studies have shown that a 2% loss in body weight will impair performance (Lewis). The body has to work harder to keep the heart pumping to produce energy and muscles firing. Not only does it feel harder when you are dehydrated, but your body is also producing energy at a slower rate.

As core temperatures increase, energy metabolism shifts from aerobic production to anaerobic and this causes a buildup of anaerobic by-products that stimulate fatigue. This process occurs at a faster rate in hot and humid conditions. Fuel source shifts from fatty acids to glucose and amino acids and creates more hydrogen and lactic acid (Burke 2015). The heart receives less blood and therefore, less oxygen is delivered to working muscles. This makes exercising even more difficult in warmer conditions. Muscles have a harder time contracting when they’re overheated and premature fatigue can set in (Nybo).

Cramping

If you lose too much water, the risk of cramping is increased. Humidity increases risk of dehydration which causes an imbalance of electrolytes, especially potassium, magnesium and sodium. These electrolytes are lost at high levels through the skin and have a significant impact on cramping (Jung).

Symptoms of dehydration

feeling thirsty
lightheaded
fatigue
dry mouth
urinating less often
infrequent, dark colored urine

Dietary recommendations in the heat

Fluid requirements are individualized. Establish your sweat rate by using a sweat test to better estimate the amount of sweat you lose in one hour of exercise. Once you know how much fluid your body loses, you can more precisely match your fluid requirements. Estimate fluid losses by using a sweat rate calculator to input your weight and fluids. Calories do not need to be increased when exercising in heat (Burke).

Start drinking fluids when you wake up. Have a glass of water before you drink coffee!
Before exercising, urine should be a pale yellow color.
Exercise in the beginning or end of the day when it’s cooler
Don’t chug water without electrolytes, this can lead to hyponatremia.
You will rehydrate faster when fluids contain electrolytes and carbohydrates. This helps stimulate thirst and retain fluids consumed (Baker & Jeukendrup 2014).

Hyponatremia is caused by drinking too much water and not enough electrolytes. Make sure to have salt or nuun tablets handy. Water follows electrolytes and when you sweat, you lose both!

The color of your urine is the best indicator of hydration. Aim for pale yellow, shade 1 or 2 on the chart is ideal. Clear urine can indicate fluid overload and hyponatremia. If your urine is dark yellow before a run, delay the start until you can drink more fluids.

References

Baker & Jeukendrup. Optimal composition of fluid replacement beverages. Comp Physiol. 2014;4:575-620.

Burke L. Nutritional needs for exercise in the heat. Comp Biochem Physiol Mol Integr Physiol. 2001; 128: 735-48.

Burke L. Clinical Sports Nutrition, 5th edition. 2015.

Cory M, et al. Resistance training in the heat improves strength in professional rugby athletes. Sci Med in Football. 2019;3:198–204.

James LJ, et al. Does Hypohydration Really Impair Endurance Performance? Methodological Considerations for Interpreting Hydration Research. Sports Med. 2019 Dec;49(Suppl 2):103-114.

Jung A, et al. Influence of Hydration and Electrolyte Supplementation on Incidence and Time to Onset of Exercise-Associated Muscle Cramps. J Athl Train. 2005; 40: 71–75.

Lewis J, et al. Does Hypohydration Really Impair Endurance Performance? Methodological Considerations for Interpreting Hydration Research. Sports Med. 2019;49:103-114.

Nybo & Sawka. Performance in the heat physiological factors of importance for hyperthermia-induced fatigue. Compr Physiol 2014;4:657-89.

Lau W, et al. Effect of oral rehydration solution versus spring water intake during exercise in the heat on muscle cramp susceptibility of young men. J of the Intl Soc of Sp Nutr. 2021; 18 (1).

Amy Stephens