17 Best Supplements for Energy and Endurance According to Experts

7. Beetroot Extract - Harnessing Dietary Nitrates for Endurance

Beetroot extract, concentrated with naturally occurring nitrates, has revolutionized our understanding of how dietary compounds can directly impact exercise performance and endurance capacity. When consumed, the nitrates in beetroot are converted to nitrites by beneficial bacteria in the mouth, then further reduced to nitric oxide in the stomach and tissues. This natural nitric oxide production pathway enhances vasodilation, improves blood flow, and increases the efficiency of mitochondrial respiration, leading to measurable improvements in exercise performance. Research consistently shows that beetroot supplementation can reduce the oxygen cost of exercise by 3-5%, allowing athletes to maintain higher intensities for longer periods or achieve the same performance with less physiological stress. Studies have demonstrated improvements in time trial performance, increased time to exhaustion, and enhanced power output across various endurance activities. The optimal protocol involves consuming 300-500mg of nitrates (equivalent to 500ml of beetroot juice or concentrated beetroot shots) 2-3 hours before exercise to allow for peak plasma nitrite concentrations. The performance benefits are particularly pronounced in moderately trained individuals and during submaximal exercise intensities. Chronic beetroot supplementation may also provide cardiovascular health benefits, including blood pressure reduction and improved endothelial function, making it valuable for both performance and long-term health.

8. Branched-Chain Amino Acids (BCAAs) - Preserving Muscle and Fighting Fatigue

Branched-chain amino acids, comprising leucine, isoleucine, and valine, represent approximately 35% of muscle protein and play crucial roles in both energy production and muscle preservation during prolonged exercise. Unlike other amino acids, BCAAs are metabolized directly in muscle tissue rather than the liver, allowing them to serve as immediate fuel sources during exercise while simultaneously signaling muscle protein synthesis pathways. Research has shown that BCAA supplementation can reduce exercise-induced muscle damage by 15-25%, decrease markers of muscle protein breakdown, and potentially delay central nervous system fatigue by competing with tryptophan for transport across the blood-brain barrier. The anti-fatigue effects are particularly relevant during prolonged endurance exercise, where BCAA oxidation can contribute significantly to energy production while helping maintain blood glucose levels. Studies demonstrate that consuming 10-15 grams of BCAAs before, during, or immediately after exercise can enhance recovery, reduce muscle soreness, and maintain performance during subsequent training sessions. The optimal ratio appears to be 2:1:1 (leucine:isoleucine:valine), though some research suggests higher leucine ratios may be more effective for stimulating protein synthesis. BCAA supplementation is particularly beneficial during caloric restriction, prolonged training periods, or when dietary protein intake is suboptimal, as it helps preserve lean muscle mass while supporting energy production and recovery processes.