What is one common substance associated with enhancements in physical performance?

Performance-enhancing drugs are commonly associated with enhancements in physical performance because they are specifically designed to increase various aspects of athletic ability, including strength, endurance, and recovery. These substances can include anabolic steroids, stimulants, hormones, and other compounds that may significantly influence physical capacities and competitive outcomes. The use of performance-enhancing drugs has been well-documented in professional sports and can lead to significant, albeit often temporary, improvements in performance metrics.

While vitamins, sports drinks, and protein bars can contribute to overall health, support recovery, and optimize performance, they do not directly enhance physiological traits to the same extent or in the same manner as performance-enhancing drugs. Vitamins help with metabolic functions, sports drinks provide hydration and electrolyte balance, and protein bars assist with muscle recovery and growth, but none of these options directly alter the body's structure or political performance capabilities in the same way. Hence, performance-enhancing drugs stand out as a specific category directly linked to enhanced physical performance.