Historically, assessors have used distance covered during the SLJ as a surrogate measure of lower-body muscular power (i.e., greater jump distance is suggestive of increased muscular power), although assumptions and limitations concerning this relationship exist.
The SLJ is a lower-body explosive strength field-based assessment whereby an individual is instructed to jump as far as they can forward (i.e., horizontally in the sagittal plane) from a bipedal standing position with the functional goal of returning to and maintaining their original bipedal standing position.
One field test that has garnered increased interest and relevance in recent years in youth populations has been the standing long jump (SLJ)-also known as the broad or horizontal jump. Likewise, lower- and upper-body explosive strength field tests (which typically measure height or distance covered, e.g., seated medicine ball toss and vertical jump) are used as proxy measures of muscular power as performance on such tests is directly related to an individual’s achieved velocity, which is proportional to the amount of force generated during an action. Thus, while attractive, the ability to produce ballistic, propulsive, high-velocity force-generating movements (e.g., jumping) should not be described as a measurement of muscular power unless the necessary Newtonian values have been computed (e.g., watts). While commonly used to describe ‘fast speed’ muscular force in practical settings, muscular power is “generated and can be measured in any dynamic movement associated with an applied force, regardless of speed” (p. By physical definition, muscular power is determined by multiplying force by displacement and dividing the product by time (or by multiplying force by velocity). However, it is important to delineate such concepts. Īs mentioned, one distinct component of muscular fitness is explosive strength (i.e., a functional characteristic), which is sometimes referred to as muscular power (i.e., a Newtonian metric). Thus, it is vital that muscular fitness is measured in youth in order to decrease or screen for potential health problems later in life. Further, muscular fitness in youth likely has longitudinal effects, which may track into adulthood. There is strong evidence which supports an inverse relationship between muscular fitness and health risk factors such as adiposity, cardiovascular disease, and metabolic disorders. Muscular fitness is an important marker of health in youth and is composed of various myo-specific dimensions such as muscular strength, explosive strength (colloquially referred to as muscular power), and muscular endurance. Implications and explanations for these results are discussed. Youth with VI who match the characteristics of the current sample may have decreased explosive strength/muscular fitness and, worryingly, their SLJ performance may not be influenced by expected factors (e.g., age). Few hypothesized variables of interest (e.g., multimorbidity) were predictive of SLJ performance. Most SLJ assessment scores were predictive of other SLJ assessment scores. In general, SLJ performance was substandard in youth with VI.
SLJ performance was investigated using a multidimensional focus (e.g., distance, Test of Gross Motor Development-3 horizontal jump, landing developmental sequences, landing joint displacement, and stabilization after landing). This study was a secondary analysis from data collected in 2018 ( N = 61, M age = 12.98 years, SD = 2.21). The purposes of this study were to investigate multidimensional SLJ performance outcomes in youth with VI (i.e., descriptives and percentages of occurrence) and to explore associations among such variables and known factors of interest (e.g., age) using robust linear bivariate regressions. Little is known concerning the SLJ in populations with disabilities such as youth with visual impairments (VI) who trend with decreased health- and performance-related outcomes. Muscular fitness, an important marker of health in youth, includes explosive strength, which can be assessed using the standing long jump (SLJ).