What is the best workout supplement?

Pre-workout supplements are designed to provide energy and aid endurance throughout a workout. They are typically taken 15-30 minutes before a workout, but can also be consumed during exercise. Below are common ingredients found in pre-workout supplements that the Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine have highlighted as having evidence-based uses in sports nutrition. [3] These supplements have also been categorized as apparently safe and having strong evidence to support efficacy by the International Society of Sports Nutrition. [4] However, it is important to consult a physician or dietitian before using these supplements, as they are not reviewed by the FDA for safety or effectiveness.

Beta-Alanine

Beta-alanine is an amino acid that is produced in the liver and also found in fish, poultry, and meat. When dosed at 4–6g/day for 2–4 weeks, this supplement has been shown to improve exercise performance, particularly for high-intensity exercise lasting 1–4 minutes, such as high-intensity interval training (HIIT) or short sprints. It has also been shown to reduce neuromuscular fatigue, particularly in older adults. [5] How does it work? During exercise the body breaks down glucose into lactic acid, which is then converted into lactate. This produces hydrogen ions, which lower muscle pH levels. This acidity reduces muscles’ ability to contract, causing fatigue. [6] Beta-alanine increases muscle concentrations of carnosine, which is a proton buffer that reduces muscle acidity during high-intensity exercise, which in turn reduces overall fatigue. [5] This supplement is often combined with sodium bicarbonate, or baking soda, which also reduces muscle acidity. A common side effect of beta-alanine supplementation is paresthesia, or a skin tingling sensation, [3] but this effect can be attenuated by taking lower doses (1.6g) or using a sustained-release instead of a rapid-release formula. [5] In short, this supplement can help you exercise at high-intensity for a longer period of time, which could potentially lead to increased muscle mass. The International Society of Sports Nutrition has asserted that “beta-alanine supplementation currently appears to be safe in healthy populations at recommended doses,” but it is important to consult with your doctor before beginning supplementation.

Caffeine

Caffeine is a stimulant that is often included in pre-workout supplements, as it has been shown to benefit athletic performance for short-term high intensity exercise and endurance-based activities. [7] It is important to understand that these studies have been conducted with Olympic and competition athletes, and thus the average individual who exercises recreationally should consult with a doctor before using caffeine as a supplement. For high performance athletes, the International Olympic Committee recommends 3–6mg caffeine/kg of body weight consumed an hour before exercise. [7,8] Evidence also suggests that lower caffeine doses (up to 3mg/kg body weight, ~200 mg) taken before and during prolonged exercise can increase athletic performance. [9,10] Mechanistically, caffeine increases endorphin release, improves neuromuscular function, vigilance, and alertness, and reduces perception of exertion during exercise. [10,11] Despite some benefits from smaller doses, larger doses of caffeine (>=9mg/kg of body weight) have not been shown to increase performance, and may induce nausea, anxiety, and insomnia. [11] The U.S. Food and Drug Administration (FDA) considers 400 milligrams of caffeine to be a safe amount for daily consumption, but some pre-workout supplements may exceed this amount in a single serving or fail to disclose the amount of caffeine they contain, so it is important to always review the label of any supplement before consumption. Caffeine powder is also marketed as a stand-alone pre-workout supplement, but the FDA has advised against using this product, as even very small amounts may cause accidental overdose. Powdered caffeine has been linked to numerous deaths—a single tablespoon (10 grams) is a lethal dose for an adult, but the product is often sold in 100-gram packages. [12]