Maximal strength performance, efficiency, and myoelectric responses with differing intra-set rest intervals during...

Area of Science:

• Exercise Physiology
• Sports Science
• Biomechanics

Background:

• Paired sets (PS) involve performing two different exercises consecutively with a rest interval between them.
• Optimizing rest intervals in PS training is crucial for maximizing training adaptations.
• Understanding the impact of varying intra-set rest periods on performance and physiological responses is essential.

Purpose of the Study:

• To investigate the effect of different rest intervals (30, 60, 90, and 120 seconds) within paired sets (PS) on total work and training volume.
• To evaluate the efficiency of training (training volume load/session duration time) under different rest conditions.
• To examine the myoelectric activity of the biceps and triceps brachii during PS exercise with varied rest intervals.

Main Methods:

• Fifteen trained men participated in the study.
• Four experimental protocols were applied: 30s, 60s, 90s, and 120s rest intervals between paired exercises.
• Surface electromyography (sEMG) of the biceps and triceps brachii was recorded during bench press/lat pull down, incline bench press/seated row, and triceps extension/biceps curl exercises.

Main Results:

• Volume load was significantly lower with 30s rest compared to 60s, 90s, and 120s rest.
• No significant differences in myoelectric activity (sEMG) were observed between the different rest interval protocols.
• Training efficiency (kg·min⁻¹) was significantly higher with 30s rest compared to all longer rest intervals (60s, 90s, 120s).

Conclusions:

• Shorter intra-set rest intervals (60s) within paired sets (PS) may be a viable strategy for enhancing volume load.
• Longer intra-set rest intervals (90s and 120s) do not appear to provide additional benefits regarding volume load or efficiency.
• The findings suggest that optimizing rest periods in PS training can lead to more efficient workouts for trained individuals.