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Work volume in strength training is not affected by rest interval strategy
W D Monteiro1, F O Venturim, A J Perez
1Salgado de Oliveira University Physical Activity Sciences Graduate Program, Rio de Janeiro, Brazil. walacemonteiro@uol.com.br
Rest intervals based on exercise-recovery-ratio (ERR) do not increase training volume more than fixed rest periods in hypertrophy resistance training. Fixed rest intervals may shorten overall session duration.
Area of Science:
- Exercise Physiology
- Sports Science
- Resistance Training
Background:
- Between-set rest intervals (RI) are crucial for recovery during resistance training.
- RI can be determined by fixed durations or exercise-recovery-ratio (ERR).
- Optimal RI strategies for hypertrophy training remain debated.
Purpose of the Study:
- To compare the influence of different ERR and fixed RI protocols on training volume.
- To investigate the effects on repetition sustainability and session duration.
- To analyze upper-body exercises targeting different muscle mass (bench press and triceps extension).
Main Methods:
- Sixteen resistance-trained men performed 5 sets to maximum repetitions.
- Five RI protocols were tested: fixed (2-min) and four ERR-based (I3, I5, I7, IP).
- Repetitions, work volume, and session duration were compared across protocols.
Main Results:
- Repetitions decreased across sets, with triceps extension showing better sustainability than bench press.
- Training volume was higher with longer RI (I7, IP, 2F) compared to shorter ones (I3, I5).
- Fixed 2-minute RI resulted in shorter session durations than ERR protocols with similar absolute rest times.
Conclusions:
- Using ERR for RI does not enhance training volume compared to fixed intervals in hypertrophy-focused resistance training.
- Fixed rest intervals may offer a more time-efficient approach to hypertrophy training.
- The choice of RI impacts both training volume and overall session duration.
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