The professional tennis season is 11 months long, and physical demand forces players to push their body to the limit for an entire year. Consequently, headlines announcing players pulling out of tournaments often cite fatigue as the culprit. Pro tennis players' fatigue, for the most part, results from the season’s demands of training, matches, and traveling – with minimal recovery time. But, you don't have to be a pro to feel the effects of fatigue in sport; some InsideTracker users lament feeling a "lack of energy" during their own tennis matches. Here are some biomarkers that might be to blame for tennis burn-out.
Burnout isn't just for the pros – which I learned the hard way
For players not competing at the professional level, the source of fatigue may be confused with inadequate food intake. Fatigue, however, may not originate from energy intake (or lack thereof) alone. Instead, the sources may be decreased physical fitness/strength, lack of sleep, or biomarkers associated with recovery that are not optimized. The solution to reducing fatigue is not necessarily to eat more, but to find out what specifically is causing the fatigue. In the case of pro tennis players, it usually involves strategically adding in recovery time. For others, the answers lie elsewhere.
At one point in my 10+ year tennis career, I experienced unrelenting exhaustion during hours of daily training and weekends of tournaments – in the heat of Florida – and it was happening very quickly. I learned through a blood test that my fatigue on the court was due to anemia (i.e., a low level of healthy red blood cells). As a result, I increased my iron intake, which lead to improved stamina and more wins. In retrospect, I believe my performance would have improved even more if I increased my sleep too.
Below is a list of biomarkers that can reveal potential sources of fatigue and recommendations of performance enhancing nutrients that may help counteract fatigue and increase overall tennis performance.
Biomarkers that affect feelings of fatigue
Glucose – Blood glucose (aka "blood sugar") is the main source of energy for the body. And while it's important to have appropriate levels for the stop-and-go nature of tennis, higher carbohydrate intake is not always the answer for better performance. Intake should be adjusted with the intensity and duration of the match in mind. Planning for a more grueling match? Be sure to increase your intake.
For example, if I’m playing doubles or expecting to win 6-0; 6-0, I don’t focus on eating a lot of carbs before the match. I consider how long I’m playing and at what intensity. When might a higher carbohydrate intake be warranted? If I’m playing a ‘baseliner' (a match consisting of continuous powerful strokes from the baseline), or playing on clay, I know it will probably be a long match, so I need to fuel appropriately.
Back-to-back matches can also present an increased challenge that requires additional fuel. Even in these cases, make sure to avoid high sugar intake. Eating too much sugar for energy before a match can put you at risk for an energy crash during it. Instead of downing your go to energy gel just before the match, try a mix a simple and complex carbohydrates the morning of - the classic peanut butter and jelly on whole grain bread provides ample and sustainable energy.
Elite players are advised to consume 6-10 g/kg/day (grams per kilogram of body weight per day), with women needing slightly less than men. However, keep in mind that these athletes train 4-6 hours per day and have a short off-season, so their carbohydrate demands are much higher than those of the average person. In addition, it is still important to tailor carbohydrate intake to daily energy expenditure.
Optimizing blood glucose – through frequent testing with InsideTracker – will prevent unstable blood sugar that hurts energy levels, triglyceride levels and blood pressure.
Dehydroepiandrosterone-sulfate (DHEAS) – DHEAS is made from cholesterol and stored in the blood until it can be transformed into different sex hormones (e.g., testosterone and estrogen). These hormones are critical for regulating energy, muscle, and bone health, and have been shown to decline with age. Because of its direct link with sex hormones, low levels of DHEAS can lead to both weakness and fatigue. InsideTracker provides simple dietary suggestions to increase DHEAS levels that can translate to better tennis performance.
Sex Hormone Binding Globulin (SHBG) – SHBG is a protein that responsible for safely transporting sex hormones, mainly testosterone, throughout the bloodstream and regulating testosterone levels within the body. Since SHBG binds testosterone, high levels may create a false pretense of low testosterone levels. However, SHBG prevents bound testosterone from leaving the body and binds it for later use by tissues in your body. Regardless, high levels of SHBG and low levels of testosterone can lead to fatigue and reduced muscle recovery in both men and women. Unsure of your hormone levels? InsideTracker not only provides answers, but also ways to improve them.
Add this nutrient to get a boost in your game
Nitric oxide (NO) is known for dilating blood vessels, but it is also important for controlling muscle contraction and maintaining glucose levels. For intermittent exercise like tennis, NO may provide sport performance benefits. NO production is known to decrease with age, so increases in NO may be especially effective for Masters athletes.
Drinking beetroot juice may increase NO. Likewise, you can supplement with the amino acid L-Citrulline, which is a precursor to NO that is produced by the body and found in watermelon (perhaps why athletes are into drinking watermelon water). If you're not looking to lug around a watermelon, you can find the same benefits in a powdered supplement form as Citrulline-malate (CM).
A recent study investigated CM supplementation on grip strength, vertical power, and anaerobic cycling performance in female tennis players (Masters athletes). They found the players had larger maximal and average vertical power when taking CM. It was concluded that consuming CM before competition may improve tennis performance.
Take control of your game
When fighting fatigue, take into consideration the different factors of tennis that require more or less energy and evaluate your food intake. Fatigue is multi-faceted and may result from unstable blood sugar, low DHEAS, or high SHBG. Optimizing your tennis performance starts with identifying the true cause of fatigue, which may be a simple blood test away.
Some other blog posts we think you'll love:
- Tired of Being Tired: How I Optimized My Iron Levels
- Getting Back on Track: Laura Ingalls' InsideTracker-Fueled Journey Back to Holistic Health
- Avoiding The Crash: How Monitoring Iron Levels Can Save Your Season
- Stress Fractures: The Relationship Between Biochemistry, Nutritional Screening and Biomechanics