Combined Strength and Endurance Training: Functional and Morphological Adaptations to Ten Weeks of Training

The literature suggests that muscular strength development can be inhibited when endurance and strength training programs are combined. The purpose of this study was to examine the effects of strength and endurance training programs, individually and in combination, on performance changes and associated muscle adaptations. Sedentary males n30 were randomly assigned to one of three training groups strength-only STR, endurance-only END, or combined strength and endurance COM. Subjects trained three days per week for ten weeks. Strength training consisted of select upper and lower body resistance exercises three maximal effort sets, five to seven repetitions per set. Endurance training consisted of continuous cycling for 50 min at 70 heart rate reserve HRR. Subjects in COM engaged in both the strength and endurance training programs on the same day. Anthropometric characteristics, strength, and peak oxygen uptake cycling were measured biopsies were taken from the vastus lateralis muscle and computed tomography CT scans were performed on mid-thigh before and after ten weeks of training. Groups STR and COM showed significant p0.05 increases in one-repetition maximum squat 23, 22 and bench press 18, 18 vertical jump 6, 9 lean body weight 3, 5 mid-thigh girth 3, 4 fast twitch FT muscle fiber area 24, 28 mean muscle fiber area 21, 23 thigh extensor 12, 14 and flexor 7, 6 areas. All groups exhibited significant increases in peak oxygen uptake following training END 18, COM 16, and STR 9. These results suggest that combining strength and endurance training programs can produce significant concurrent gains in muscular strength and power, muscle hypertrophy, and peak oxygen uptake.... combined training, strength, endurance, muscle histology.