Strategic Daytime Napping Enhances Agility and Lowers Perceived Exertion But Does Not Improve Fatigue Resistance in Adolescent Soccer Players

Summary

Background

Daytime napping is increasingly incorporated into athletic recovery routines to manage sleepiness and support alertness. However, the effects of different nap durations on high-intensity anaerobic performance tasks remain insufficiently characterized, particularly in team-sport settings. Nap duration and circadian timing may influence psychomotor readiness, perceived exertion, and fatigue-related responses, yet existing evidence is limited and inconsistent in adolescent athlete populations. This study is designed to examine the acute effects of two daytime nap durations within a controlled experimental framework.

Methods

This study will employ a randomized, crossover design involving sixteen competitive male adolescent soccer players classified as intermediate chronotypes. Each participant will complete three experimental conditions in a randomized order: no nap (N0), a 25-minute nap (N25), and a 45-minute nap (N45), with standardized washout periods between sessions. Nap compliance will be objectively monitored using wrist-worn actigraphy.

Following each condition, participants will observe a standardized 60-minute post-nap wakefulness period prior to performance testing. Agility performance will be assessed using the Pro Agility Test, and anaerobic endurance will be evaluated using a repeated-sprint ability (RSA) protocol. Psychophysiological measures will include ratings of perceived exertion (RPE), the Hooper Index, visual analogue scales (VAS) for subjective alertness, and mood states assessed via the Profile of Mood States (POMS). These outcomes will be collected to compare responses across nap conditions.

Objectives

The primary objective of this study is to compare the acute effects of two daytime nap durations (25 minutes vs 45 minutes) on agility performance in adolescent soccer players without a habitual napping routine. Secondary objectives include examining nap-related differences in repeated-sprint performance indices, perceived exertion, subjective alertness, and mood states.

Keywords

daytime nap; athletic recovery; agility; repeated-sprint ability; perceived exertion; mood; chronotype

Conditions

• Sleep Deprivation
• Athletic Performance
• Fatigue

Interventions

BEHAVIORAL

Pro Agility Test

The Pro Agility Test (20-yard shuttle run) evaluates change-of-direction speed. Participants started from the center point, ran 5 yards to the left, then 10 yards to the right, and finally 5 yards back to the center. The total distance was 18.28 meters, and the time to complete the sequence was recorded. Agility and RSA timings were recorded using a dual-beam electronic timing system (SmarTracks, Germany) with a sampling frequency of 1,000 Hz, positioned at the start and finish lines at hip level. This minimized human error and ensured millisecond precision.

BEHAVIORAL

Repeated-Sprint Ability (RSA) Test

The RSA test measures an athlete's ability to repeatedly produce maximal sprint efforts with limited recovery. This study employed 6 × 30-meter sprints with 20-second rest intervals between each sprint, a protocol commonly used in team sports to assess anaerobic endurance.

BEHAVIORAL

Rate of Perceived Exertion (RPE)

RPE was assessed using the Borg Scale (6-20), which captures the participant's subjective effort during physical activity. RPE was recorded immediately after each sprint during the RSA Test, and the average RPE score represented overall perceived exertion for the session.

Sponsors & Collaborators

• Inonu University

  collaborator OTHER

• Princess Nourah Bint Abdulrahman University

  collaborator OTHER

• Uludag University

  lead OTHER

Principal Investigators

• Mertkan Öncü, MsC · Uludag University

• Monira I. Aldhahi, PhD · Nourah bint Abdulrahman University

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

SINGLE

Model

CROSSOVER

Eligibility

Min Age

16 Years

Max Age

19 Years

Sex

MALE

Healthy Volunteers

No

Timeline & Regulatory

Start

2024-05-10

Primary Completion

2024-05-18

Completion

2024-05-18

Countries

• Turkey (Türkiye)

Study Locations