Workout Fuel

Dwayne N. Jackson, PhD

Past research suggests that eating an abundance of fresh fruits and vegetables, high in antioxidants, can improve lung function. Unfortunately, many sports require athletes to limit their diet (and restrict calories from fruits and high-carb veggies) in an effort to meet weight class cut-offs or maintain light and lean physiques.

In the fitness supplement world, antioxidant supplements are generally associated with decreased exercise-induced muscle damage, faster recovery, and decreased sick time. However, research published in the European Journal of Applied Physiology shows us that taking a blend of antioxidant vitamins (vitamin C, E, and beta-carotene) and minerals (zinc, selenium, copper, and manganese) can significantly improve lung function and decrease shortness of breath and perceived exertion during exhaustive treadmill exercise. This is especially relevant for athletes competing in tournament sports (like wrestling, MMA, and boxing) and where performances last for several minutes and include repeated efforts or bouts.

ACTION POINT: If your diet consists of less than 5 servings of fruit and vegetables per day, then you can boost your lung function and decrease perceived exertion by taking an antioxidant supplement. The best way to get all the antioxidant support you need is to take a multi-vitamin and mineral supplement designed for athletes. Make sure it contains the following minimum doses of vitamins and minerals: C (500 mg), E (400 IU), beta-carotene (15,000 IU), zinc (7.5 mg), selenium (50 mg), copper (1 mg), and manganese (2.5 mg).

Reference: Chenoweth LM, Smith JR, Ferguson CS, Downey AE, Harms CA. The effects of antioxidant vitamin supplementation on expiratory flow rates at rest and during exercise. Eur J Appl Physiol. 2015 Oct;115(10):2049-58.

Beet That

Increasing dietary nitrate intake is becoming a popular supplement strategy among strength and endurance athletes, as nitrates can be reduced to nitric oxide (NO) in the body to widen blood vessels and increase blood flow to active muscles. Beyond the purported blood flow boosting effects, high dietary nitrates have also been shown to increase exercise efficiency during endurance training.

One of the best ways to accomplish all of this is with high-nitrate beetroot extract. A recent study published in the European Journal of Applied Physiology investigated the effects of dietary nitrate on exercise performance and cognitive function using a protocol designed to mimic work patterns observed in team sports. In the study, 16 male team-sport players received nitrate-rich beetroot juice and placebo (nitrate-depleted beetroot juice) for seven days. On day seven of supplementation, subjects completed intermittent “all out” sprint training on a cycle ergometer while cognitive tasks were simultaneously performed. They found that beetroot juice gave a 3.4% improvement in total work completed and mitigated the decline in reaction time observed in the placebo condition.

ACTION POINT: This study provides great support for the use of beetroot extract in athletes who play intermittent power sports like hockey, football and tennis, where reaction time is important. There are many products available on the market that aim to boost dietary nitrate. Based on differences in potency, we recommend choosing beetroot extract or juice and taking as directed.

Reference: Thompson C, Wylie LJ, Fulford J, Kelly J, Black MI, McDonagh ST, Jeukendrup AE, Vanhatalo A, Jones AM. Dietary nitrate improves sprint performance and cognitive function during prolonged intermittent exercise. Eur J Appl Physiol. 2015 Sep;115(9):1825-34.