Effects of intra-session concurrent endurance and strength training sequence on aerobic performance and capacity

Aim: To examine the effects of the sequencing order of individualised intermittent endurance training combined with muscular strengthening on aerobic performance and capacity. Methods: Forty eight male sport students ( mean (SD) age 21.4 (1.3) years) were divided into five homogeneous groups according to their maximal aerobic speeds (v(V) over dot O(2)MAX). Four groups participated in various training programmes for 12 weeks ( two sessions a week) as follows: E ( n = 10), running endurance training; S ( n = 9), strength circuit training; E+S ( n = 10) and S+E ( n = 10) combined the two programmes in a different order during the same training session. Group C ( n = 9) served as a control. All the subjects were evaluated before (T0) and after (T1) the training period using four tests: ( 1) a 4 km time trial running test; ( 2) an incremental track test to estimate v(V) over dot O(2)MAX; ( 3) a time to exhaustion test (t(lim)) at 100% v(V) over dot O(2)MAX; ( 4) a maximal cycling laboratory test to assess (V) over dot O(2)MAX. Results: Training produced significant improvements in performance and aerobic capacity in the 4 km time trial with interaction effect ( p< 0.001). The improvements were significantly higher for the E+S group than for the E, S+E, and S groups: 8.6%, 5.7%, 4.7%, and 2.5% for the 4 km test ( p< 0.05); 10.4%, 8.3%, 8.2%, and 1.6% for v(V) over dot O(2)MAX ( p< 0.01); 13.7%, 10.1%, 11.0%, and 6.4% for (V) over dot O(2)MAX (ml/kg(0.75)/min) ( p< 0.05) respectively. Similar significant results were observed for tlim and the second ventilatory threshold (% (V) over dot O(2)MAX). Conclusions: Circuit training immediately after individualised endurance training in the same session (E+S) produced greater improvement in the 4 km time trial and aerobic capacity than the opposite order or each of the training programmes performed separately.