Smoking has a detrimental impact on physical endurance due to its effects on lung capacity and cardiovascular health. The harmful chemicals in cigarettes impair oxygen delivery to muscles, leading to decreased stamina and increased fatigue. Smokers may experience reduced aerobic performance, as nicotine constricts blood vessels and inhibits the body’s ability to utilize oxygen efficiently. This results in a lower overall exercise capacity and performance. Quitting smoking can enhance fitness levels and overall health, significantly improving endurance over time.