What components of fitness does fartlek training improve?

Fartlek training improves several components of fitness, primarily cardiovascular endurance and speed. By incorporating varying intensities and paces, it enhances aerobic capacity while also promoting anaerobic fitness through bursts of high-intensity effort. Additionally, it can improve muscular endurance and mental toughness, as the unpredictable nature of the workout challenges both the body and mind. Overall, fartlek training is a versatile method that effectively boosts overall athletic performance.