Effects of Resistance Exercise Timing on Midday Muscle Performance in Athletes

Manisa Celal Bayar University13 enrolled

Overview

This study investigated whether the timing of a resistance-based post-activation performance enhancement (PAPE) intervention performed during the morning influences muscle performance and muscle electrical activity during a standardized midday assessment in trained male athletes. Participants completed a control condition and three PAPE conditions performed at different times during the morning. The PAPE intervention consisted of back squat, kettlebell swing, and barbell hip thrust exercises. In all conditions, muscle performance was assessed between 12:00 and 12:15 using an isokinetic dynamometer, while surface electromyography (sEMG) of the rectus femoris muscle was recorded. The study compared relative peak torque and sEMG spectral power across the different PAPE timing conditions and the control condition.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

NONE

Enrollment

Conditions

Neuromuscular Performance Post-Activation Performance Enhancement (PAPE)

Interventions

Resistance-Based PAPE InterventionBEHAVIORAL

The resistance-based PAPE intervention consisted of three exercises performed in the following order: back squat, kettlebell swing, and barbell hip thrust. Participants performed one set of six repetitions at 80% of their individual estimated one-repetition maximum (e1RM) for each exercise, with a 1-minute rest interval between exercises. The intervention was preceded by a 5-minute standardized cycling warm-up at 60 rpm followed by 5 minutes of passive rest. The same PAPE protocol was performed in the T1, T2, and T3 conditions at different times before the standardized midday performance assessment.

Eligibility

Sex: MALEHealthy volunteers:

Medical Language ↔ Plain English

Inclusion Criteria: * Regularly participating in systematic sport-specific training (minimum training age of 3 years) * Able to comply with pre-testing restrictions (avoidance of intense physical activity for 72 hours and caffeine for 2 hours prior to testing sessions) Exclusion Criteria: * Any musculoskeletal, orthopedic, or health condition preventing safe participation in maximal isokinetic exercise testing * Current or recent injury affecting lower-limb strength or performance testing

Outcomes

Primary Outcomes

Relative Peak Torque (RPT)

Relative peak torque (RPT) was determined from the highest peak torque value obtained during four maximal knee extension repetitions performed on an isokinetic dynamometer at 60°·s-¹. Peak torque was normalized to body mass and expressed as N·m·kg-¹.

Time frame: Measured once per condition (control, T1, T2, T3) at a fixed assessment time (12:00-12:15 PM). PAPE was performed 3.5 hours (T1), 1.5 hours (T2), or immediately (T3) before assessment. Each condition was separated by at least 48 hours.

Rectus Femoris sEMG Spectral Power

Surface electromyography (sEMG) of the rectus femoris muscle was recorded during the maximal isokinetic knee extension repetitions. Spectral power was calculated from the processed sEMG signal using fast Fourier transform (FFT) analysis and expressed as µV²/Hz.