Isolation exercises for strength training require longer recovery time

The more isolation exercises that strength athletes use in their workout, the longer their muscles need to recover. Sports scientists at the University of Brasilia published their findings in the Journal of Strength and Conditioning Research. Bodybuilders and fitness fanatics who like to do a full-body workout three times a week are better off doing as few isolation exercises as possible and as many multi-joint exercises as possible.

The researchers performed an experiment on 16 ‘highly resistance trained’ men. They got their subjects to do 8 sets of curls with one arm using a weight with which they could just manage 10 reps.

The curl [see illustration of the classical way below right; the subjects did it with just one arm] is an isolation exercise, or as scientists prefer to call it, a single joint exercise: only the elbow joint moves, and the exercise only stimulates the biceps.


The men trained their other arm by doing the seated row [classical way of performing this is shown above on the left; the subjects did it with only one arm]. The men also did 8 sets of this exercise, also using a weight with which they could just manage 10 reps.

The seated row is a combined exercise, or multi-joint exercise: the elbow is not the only joint that moves; the shoulder joint and shoulder blades move too. The exercise stimulates not only the biceps but also muscles in the shoulder joint and – above all – muscles in the upper back.

During the 4 days after the workout the men experienced more muscle soreness in the arm that had done the curl than in the arm that had done the seated row.


During this same period the researchers measured the torque – or strength – in the subjects’ biceps. The figure below shows that the subjects took longer to recover strength in the arm that had done the curls than in the arm that had done seated rows.


“Single joint elbow flexor exercise induced greater elbow flexor peak torque decreases and greater delayed-onset muscle soreness compared to multi-joint elbow-flexion exercise”, the researchers concluded. “In addition, the time course of elbow flexor muscle recovery was greater after single- compared to multi-joint exercise in highly strength trained subjects, even with subjects performing greater a workload during the multi- compared to single-joint exercise.”

“The results of the present study suggest that strength and athletic trainers should take into consideration the effect of multi- and single-joint exercises on recovery during strength training periodization. Depending on the type of exercise used (i.e. single- and multiple joints), resistance trained subjects or athletes might not be able to perform strength or power activities at their best until 24 or 48 hours after the previous exercise bouts.”

Dissociated Time Course of Muscle Damage Recovery Between Single- and Multi-Joint Exercises in Highly Resistance-Trained Men.


This study compared the time course of elbow flexor muscle recovery after multi- and single-joint exercises in highly resistance-trained men. Sixteen men (24.5 ± 5.5 years) performed, in a counterbalanced order, 8 sets of 10 repetition maximum (RM) unilateral seated row exercise and 8 sets of 10RM unilateral biceps preacher curl exercise using the contralateral arm. Maximum isometric peak torque (PT) and delayed onset muscle soreness (DOMS) were recorded at baseline (pre), 10 minutes, 24, 48, 72, and 96 hours after each exercise protocol. There was a significant decrease (p ? 0.05) in elbow flexor PT 10 minutes after both the multi- and single-joint exercise sessions. However, PT decrease was greater after single-joint (26.8%) when compared with multi-joint (15.1%) exercise (p ? 0.05). In addition, elbow flexor PT was lower (8.4%) than baseline 24 hours after the single-joint exercise (p < 0.01), whereas PT returned to baseline 24 hours after the multi-joint exercise. Compared with baseline, DOMS increased at 24, 48, and 72 hours after single-joint exercise (p ? 0.05). However, DOMS returned to baseline levels after 72 hours after multi-joint exercise. In addition, DOMS after single-joint exercise was greater (p ? 0.05) than after multi-joint exercise at 24, 48, and 72 hours after exercise. Our data suggest that after a resistance training session, highly resistance-trained men experience dissimilar elbow flexor strength recovery between single-joint and multi-joint exercises. Likewise, elbow flexor DOMS is greater and takes longer to recover after single-joint exercise. PMID: 25807025 DOI: 10.1519/JSC.0000000000000899 [PubMed - indexed for MEDLINE] Source: