title: Low-load Slow Movement Squat Training Increases Muscle Size and Strength but Not Power.
abstract: We tested a hypothesis that low-load squat training with slow movement and tonic force generation (LST) would increase muscle size and strength but not necessarily power. Healthy young men were assigned to LST [50% one-repetition maximum (1-RM) load, 3 s for lowering/lifting without pause: n=9] or low-load normal speed (LN: 50% 1-RM load, 1 s for lowering/lifting with 1-s pause; n=7) groups. Both groups underwent an 8-week squat training program (10 repetitions/set, 3 sets/day, and 3 days/week) using the assigned methods. Before and after the intervention, quadriceps femoris muscle thickness, maximal torque during isometric hip extension and knee extension, 1-RM squat, lifting power from squatting position and rate of electromyography rise (RER) in knee extensors during the task, leg extension power and vertical jump height were measured. After the intervention, the LN group showed no changes in all the variables. The LST group significantly (P<0.05) increased muscle thickness (6-10%), isometric hip extension torque (18%) and 1-RM squat (10%), but not isometric knee extension torque, lifting power and RER, leg extension power and vertical jump height. These results suggest that LST can increase muscle size and task-related strength, but has little effect on power production during dynamic explosive movements.
authors.affiliation: Sports and Life Science, National Institute of Fitness and Sports in Kanoya.
authors.forename: S
authors.initials: S
authors.lastname: Usui
authors.affiliation: Faculty of Sport Sciences, Waseda University, Tokorozawa, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Maeo
authors.affiliation: Sports and Life Science, National Institute of Fitness and Sports in Kanoya.
authors.forename: K
authors.initials: K
authors.lastname: Tayashiki
authors.affiliation: Sports and Life Science, National Institute of Fitness and Sports in Kanoya.
authors.forename: M
authors.initials: M
authors.lastname: Nakatani
authors.affiliation: Sports and Life Science, National Institute of Fitness and Sports in Kanoya.
authors.forename: H
authors.initials: H
authors.lastname: Kanehisa
mesh_terms: D004576:Electromyography; D006621:Hip Joint / Q000502:physiology; D006801:Humans; D007537:Isometric Contraction; D007719:Knee Joint / Q000502:physiology; D007866:Leg; D008297:Male; D009068:Movement; D053580:Muscle Strength / Q000502:physiology*; D009929:Organ Size; D011187:Posture; D052097:Quadriceps Muscle / Q000502:physiology*; D019415:Torque; D014891:Weight Lifting / Q000502:physiology*; D055815:Young Adult