Load-controlled moderate and high-intensity resistance training programs provoke similar strength gains in young women

Abstract

Introduction: While current exercise guidelines recommend progressive, high-intensity resistance training (RT) to promote muscle hypertrophy and strength gains, controversy exists regarding the efficacy of lighter-load RT. We compared 2 work-matched RT interventions that differed in training intensity.

Methods: Fifteen women underwent 10 weeks of unilateral knee extensor RT. One leg was trained at increasing intensity (intensity leg, InL, 50-80% 1-repetition maximum [1-RM]), and training progression in the contralateral leg (volume leg, VoL, 50% 1-RM) was based on increasing training volumes. Quadriceps muscle size (ultrasound, dual energy X-ray absorptiometry) and strength (isokinetic dynamometry) were assessed on 4 occasions.

Results: Both training programs induced significant, yet comparable increases in muscle size (InL: +4.6-12%, VoL: +3.1-11%) and strength (InL: +10-16%, VoL: +10-14%).

Conclusions: Training at lower than commonly suggested intensities may be an equally effective alternative form of RT. Factors other than training intensity, such as the total mechanical work during training, may strongly affect the training response.

Keywords: DXA; hypertrophy; quadriceps femoris; strength training; ultrasound.