Which method is least effective for improving endurance in young athletes?

Single-session workouts are considered the least effective method for improving endurance in young athletes primarily because endurance training is most beneficial when it is applied consistently over time rather than in isolated sessions.

Endurance improvement is achieved through repetitive training that gradually increases in intensity and duration, allowing the body to adapt and build stamina. Single-session workouts may not provide enough volume or intensity to stimulate the physiological adaptations necessary for endurance enhancement. Instead, methods such as interval training, continuous steady-state training, and high-intensity training involve structured, repeated bouts of exercise that contribute to a greater training effect and sustained improvement in endurance capabilities over time.

In contrast, a solitary workout lacks the systematic progression and frequency required to develop and enhance the cardiovascular and muscular systems effectively. Thus, while a single-session workout may offer some immediate benefits, it falls short of fostering long-term endurance development in young athletes.