title: Predicting Maximal Dynamic Strength From the Load-Velocity Relationship in Squat Exercise.
abstract: The aim of this study was to develop a rapid indirect method to determine an individual's maximal strength or 1 repetition maximum (RM) in untrained subjects during half-squat exercise. One hundred and five physically active young subjects (87 men and 18 women) performed a submaximal and a maximal load test during half-squat exercises on a Smith machine. In the submaximal test, subjects completed 3 repetitions with a load equivalent to body weight. The velocity and power of barbell displacement were recorded during the upward movement from 90° of knee flexion. All repetitions were performed at maximum velocity. In a subsequent 1-2RM test, the 1RM for the exercise was calculated. The variables' load and mean velocity (V(mean)) were used to construct an adjusted 1RM prediction model, which was capable of estimating the 1RM with an accuracy of 58% (F(exp) = 72.82; 2; 102 df; p ≤ 0.001). Our results indicate a good correlation between the mean displacement velocity of a load equivalent to body weight and 1RM. This relationship enables a safe and fast estimation of 1RM values in half-squat exercise (1RM = -61.93 + [121.92·V(mean)] + [1.74·load]) and provides valuable information to untrained subjects who are starting resistance training programs.
authors.affiliation: 1Department of Physical Education and Sport, Faculty of Sports Sciences, University of Granada, Granada, Spain; and 2Department of Statistics and Operations Research, Faculty of Medicine, University of Granada, Granada, Spain.
authors.forename: Bruno
authors.initials: B
authors.lastname: Bazuelo-Ruiz
authors.forename: Paulino
authors.initials: P
authors.lastname: Padial
authors.forename: Amador
authors.initials: A
authors.lastname: García-Ramos
authors.forename: Antonio J
authors.initials: AJ
authors.lastname: Morales-Artacho
authors.forename: María T
authors.initials: MT
authors.lastname: Miranda
authors.forename: Belén
authors.initials: B
authors.lastname: Feriche
mesh_terms: D000328:Adult; D001835:Body Weight; D003430:Cross-Sectional Studies; D005080:Exercise Test / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D053580:Muscle Strength / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology*; D055070:Resistance Training / Q000379:methods*; D016474:Weight-Bearing / Q000502:physiology; D055815:Young Adult