Field-based tests of aerobic fitness that can be administered quickly and do not require maximal effort are desirable. The purpose was to develop and validate quarter-mile walk tests for 10--13-year-olds. Participants (N = 59) walked one mile on two different days. Walk times, heart rates, body mass, physical activity, and aerobic fitness were…

This study compared the weekly training load (TL) variation across different measures. Fifty-two runners reported their heart rate and distance ran for each training session during four weeks of training. Heart rate measures were used to calculate the weekly TRaining IMPulse (W-TRIMP), whereas the distance ran was used to calculate the weekly…

We investigated the associations and differences between dynamic strength index (DSI) calculated from different types of vertical jump (countermovement jump; CMJ and squat jump; SJ) and different isometric knee joint angles (30, 60 and 90[degrees]), and associations with force-velocity (FV) profile and its constituent variables (maximal…

Confirmatory factor analysis (CFA) is a commonly used statistical technique. Recommendations for evaluating CFA highlight scholars should outline the expected model, conduct data screening, report model estimation and evaluation, and report key information about results to provide evidence for latent variables. The purpose of the current study was…

This study aimed to develop and validate machine learning models to predict intensities in children and adolescents with cystic fibrosis (CF) across different accelerometry brands and placements. Thirty-five children and adolescents with CF (11.6 ± 2.8 yrs; 15 girls) and 28 healthy youth (12.2 ± 2.7 yrs; 16 girls) performed six activities whilst…

This study investigated whether exercise and physical activity identity are conceptually distinct factors. Undergraduate students (N = 647; M[subscript age] = 19.54 ± 1.86 years; 61% female) completed an online survey including the Exercise Identity Scale and a modified physical activity version. Confirmatory factor analysis largely supported a…

The purpose was to evaluate reliability of measurements during drop jump (DJ) and magnitude of differences in vertical jump height (VJH) when calculated using two variables: time-in-the-air and center-of-mass velocity. Thirty-seven handball players performed three single-leg and double-leg DJs on a portable force plate during two sessions. Sixteen…

The flexion relaxation ratio (FRR) of the lumbar extensor muscles is often assessed in experimental and clinical studies. This study evaluated within- and between-session test--retest reliability and measurement error for different FRR formulations. Participants completed two identical data collection sessions 1-week apart. Spine flexion and…

A number of familiarization trials are needed for reliable measurement, particularly for inexperienced subjects. Researchers have studied and developed familiarization protocols that vary by exercise and study population. The pace of familiarization and fatigue may be an individual-level characteristic, so a population-level protocol may not fit…

Small sample sizes contribute to several problems in research and knowledge advancement. This conceptual replication study confirmed and extended the inflation of type II errors and confidence intervals in correlation analyses of small sample sizes common in kinesiology/exercise science. Current population data (N = 18, 230, & 464) on four…

As part of a validation study of the Exercise Planning and Scheduling (EPS), and Goal-Setting (EGS) Scales, which were translated from English to Brazilian Portuguese, we aim to: present evidence of reliability and validity for the translated scale; and, explore the effects of non-labeled response categories of rating scales. The sample comprised…

Derived from the Expectancy-Value Theory (EVT) model, cost has drawn scholarly interest for being predicative of avoidance motivation. The study is an effort to develop and validate an instrument to measure students' perceived costs in physical education. Through literature review and student interviews, a draft of 39 items under seven domains was…