Longer rest periods and short durations of time-under-tension during strength training produce limited what effects?

Longer rest periods combined with shorter durations of time-under-tension during strength training primarily lead to limited hypertrophic effects. Hypertrophy refers to the increase in muscle size, and it is largely stimulated by prolonged tension in the muscle fibers. When the time-under-tension is reduced, it restricts the muscle's ability to undergo the metabolic stress and micro-tears that contribute to muscle growth.

Furthermore, longer rest intervals can promote maximal strength by allowing for optimal recovery between sets, which can enhance performance in subsequent lifts. However, these longer recovery periods do not favor the metabolic stress and increased muscle fatigue that are critical for hypertrophy. Therefore, while longer rest might improve strength gains, it does not effectively stimulate the muscular adaptations associated with size increases, identifying limited hypertrophic effects as the correct characterization of this training approach.