Effects of 24 weeks of single session combined strength and endurance training on body composition and fitness : examination of order effect

Abstract

Küüsmaa, Maria 2013. Effects of 24 weeks of single session combined strength and endurance training on body composition and fitness: examination of order effect. Department of Biology of Physical Activity, University of Jyväskylä. Master’s Thesis in Science of Sport Coaching and Fitness Testing. 82 pp.

Endurance and strength training are often performed concurrently. The question of whether the order of exercise yields to different adaptations in body composition, when strength (S) and endurance training (E) are combined into the same training session, has received only limited scientific attention. In addition, neuromuscular and cardiorespiratory adaptations to single session combined training have shown conflicting results, especially when examining the intra-session sequence. The purpose of this thesis was to examine the effect of strength and endurance training sequence on body composition as well as on aerobic and strength performances.

56 previously physically active men (18-40 yrs) completed a progressive 24-week single session strength and endurance training period. They were assigned into three groups. One performed E always before S in the training session (E+S; n=14), the other completed the same training sections with the opposite order (S+E; n=18), and the control group continued their habitual physical activity (Control; n=24). In order to determine prolonged training adaptations the measurements were conducted in the beginning, after 12 weeks, and after completing 24 weeks of training. All the subjects were tested for the body composition using DXA, upper and lower body strength (isometric and dynamic leg press and isometric shoulder press) and for the aerobic power during an incremental cycling test.

The main finding was a significant increase in total body lean mass throughout the 24-week period without significant between-group difference (E+S 3.3%; S+E 2.6%; p≤0.001). In addition, leg lean mass also increased similarly in both E+S (6.0%; p˂0.000) and in S+E (4.9%; p˂0.000). Body weight had a tendency to increase in both training groups but reached the significance only in the S+E group (2.3%; p=0.013). Physical performance increased similarly in both training groups. Dynamic and isometric leg strength increased (p˂0.001) 12.6% and 11.6% in the E+S group and 17.0% and 13.2% in the S+E group. Upper body isometric strength increased (p˂0.05) 10.2% and 7.6% in E+S and S+E, respectively. Aerobic power increased (p=0.000) in both E+S (11%) and S+E (16.2%).

In conclusion, this study showed that the current 24-week single session combined strength and endurance training program significantly increased total body and leg lean mass, independent of the strength and endurance order. Training sequence had also little influence on strength and endurance adaptations to concurrent training, as the improvements of the same magnitudes were observed for both E+S and S+E group. Independent of the training sequence the current training program caused positive changes in body composition and physical fitness and can be considered beneficial for long term health maintenance.