Comparison of the effects of two different methods of concurrent training
(continuous and interval) on body composition, aerobic power and muscle

Purpose: The purpose of this study was to compare the effect of two different methods of concurrent training
(continuous and distinct) on body composition, aerobic power and muscle endurance in non-athlete male students.
Method: For this reason, 42 non-athlete students (age, 22.02±1.91 yrs; height, 175.83±5.88 cm; weight,
69.01±8.27 kg; BF, 13.71±3.33%) volunteered to participate in this study. Subjects were randomly assigned to 3
groups: Interval Resistance-Endurance (IRE) (n=14), Continuous Resistance-Endurance (CRE) (n=14), and
Control (C) (n=14). Subjects performed 2 sessions per week for 12 weeks. Strength training includes Bench press,
Lat pull down and cable triceps for upper body; squat, leg press and calf raise for lower body muscles that
performed with 2-3 min rest interval between sets and exercises, and total time in each session was about 30-45
min. These exercises start with 2 sets, 10 repetitions with 60% 1RM in begining of program and reached to 3 sets,
4 repetitions & 90% 1RM in the last week. Aerobic training involved 20 min interval running using long and short
distance by 70% maximal heart rate in start and raised to 45 min running by 95% HRmax in last week. IRE group
performed aerobic training in one session and resistance training in other session in each week. In contrast, CRE
group performed both aerobic and resistance training in each session together. Control group performed no regular
exercise during this period. For data analysis, paired t test, ANOVA and tukey post hoc tests were used. Result:
The findings showed BF% reduced significantly in both experimental groups compare to C group (P<0.05). Pullup
and sit-up records of IRE and CRE groups in post-test was higher than pre-test, but this improvement was
significantly smaller in IRE group in sit-up test (P<0.05). VO2max increased significantly after training in both
experimental groups than control but in IRE group it improved significantly higher than CRE group (10.88 vs. 9.07
ml·kg−1·min−1; P<0.05). Conclusion: In general, it can be suggested that for improving aerobic power, the aerobic
training must performed alone not in concurrent form. But, concurrent training may be more useful for body
composition and muscular endurance than resistance or endurance training alone.