High volume resistance training is employed by coaches during training emphasizing enhanced body composition, hypertrophy, and work capacity. However, high volume training may cause levels of fatigue that impact strength and power performances. It is not well known if using fatigue-management strategies such as heavy and light days affect these performances.
PURPOSE: To compare changes in kinetic variables following high volume resistance training employing heavy and light days.
METHODS: Eight strength trained males (age = 27.4 + 4.2 years, body mass = 90.8 + 11.8 kg, isometric peak force = 4397.1 + 636.9) participated in the study. Pre-and post-training each subject was evaluated for isometric peak force (IPF), allometrically-scaled isometric peak force (IPFa), and rate of force development at 90 ms (RFD90) during an isometric mid-thigh pull test on a dual force platform sampling at 1000Hz. The training protocol consisted of resistance training 3 days/wk with each week progressing in intensity. Each 3rd training day was a light day (10% lighter than day 1). Paired-samples t-tests were calculated pre-post the 3 weeks to assess changes associated with training. Magnitudes of change were examined using percent change and effect size using Cohen’s d.
RESULTS: The change in body mass (BM) was significantly higher (90.8 + 11.8 kg to 92.5 + 11.7 kg) (p = 0.03) while no statistical differences were observed in IPF (4397.1 + 636.9 N to 4380.4 + 432.9 N), IPFa (218.0 + 25.5 N/kg0.67 to 215.5 + 23.2 N/kg0.67), or RFD90 (10155.6 + 5511.3 N·s-1 to 9208.3 + 4547.3 N·s-1) (p > 0.05). Percent change for BM, IPF, IPFa, and RFD90 were as follows: 1.9%, -0.4%, -1.2%, -9.3%, respectively. Effect sizes for BM (d = 0.15), IPF (d = 0.03), IPFa (d = 0.10), and RFD90 (d = 0.19) indicated trivial effects pre-post high volume training.
CONCLUSIONS: High volume resistance training is often concomitant with reductions in strength performance. The results of the study indicate that force outputs were spared following 3-wks high volume training when employing heavy and light days. Although not significant, a reduction in RFD90 of 9.3% is practically significant for athletes. It seems that while strength variables were largely unaffected, explosiveness (i.e. RFD90) may be more sensitive to high training volumes regardless the fatigue management strategies used.