To Compare Chronotype Dependent Effects of Whole-Body Vibration on Neuromuscular Performance in Male Collegiate Athletes: A Randomized Cross-over Study

INTRODUCTION

Chronotype is an individual’s inclination towards morningness or eveningness that is typically assessed via self-assessment questionnaires (Terman et al., 2001;Horne & Ostberg, 1976). Chronotype is divided into three categories: morning type, evening type, and neither type; it reflects the time of day when numerous psychophysiological variables peak (Jacopo Antonino Vitale & Weydahl, 2017).

 NEED OF THE STUDY·       This research will add to our understanding of how whole-body vibration affects neuromuscular performance such as Strength, Power, Speed, Agility, and Balance.

·       This research will also help determine when whole body vibration is most useful and which types of athletes (morning vs. evening) gain the most from WBV. As a result, it is vital to know the effect of WBV on NMP in athletes of diverse chronotypes.

·       To the best of my knowledge, no study has incorporated the acute effects of WBV at two separate times based on chronotype. The study’s novelty is the effectiveness of WBV on neuromuscular performance based on different chronotypes and at two separate times.

 RESEARCH QUESTIONIs there any change in the NMP of a collegiate male athlete depending on his Chronotype, after single-bout of whole-body vibration applied at two separate times of the day?

OBJECTIVES OF THE STUDY

·       To find the acute effects of WBV on neuromuscular performance in male collegiate athletes.

·       To implement the WBV as a treatment for enhancing neuromuscular performance utilizing %Maximum voluntary isometric contraction(%MVIC), Countermovement jump height, 20m single sprint, T-test, and Y-balance test.

·       To find out when WBV is most useful (morning vs evening time), as well as which types of athletes (morning vs. evening type) gain the most from WBV.

HYPOTHESIS OF THE STUDYNull HypothesisThere will be no statistically significant variations in Neuromuscular performance amongst male collegiate athletes of different chronotypes who use WBV at two distinct time periods.

Experimental hypothesis

There will be statistically significant variations in Neuromuscular performance amongst male collegiate athletes of different chronotypes who use WBV at two distinct time periods.

SIGNIFICANCE OF THE STUDY

This research will add to our understanding of whether chronotype can affect the training and thus the performance of an athlete. It will also help us to determine how whole-body vibration affects neuromuscular performance such as Strength, Speed, Power, Agility, and balance. This research will also help determine when whole body vibration is most useful and which types of athletes (morning vs. evening) gain the most from WBV. As a result, it is vital to know the effect of WBV on NMP in athletes of diverse chronotypes.

PROTOCOL FOR DATA COLLECTION:

Subjects will be recruited from different department of Jamia Millia Islamia, M.A.K Pataudi sports complex and the surrounding community based on inclusion and exclusion criteria, and they will be informed about the study. The goal of the study and any potential dangers will be addressed to the individual. They will be provided with informed consent after being informed of their rights as study subjects. A self-administered questionnaire will be used to choose subjects. A self-report version of revised Morningness-Eveningness Questionnaire (MEQ-REV-SR) will be used to divide people into three chronotypes: morning, intermediate, and evening MEQ (Terman M et al., 2001;Horne & Ostberg, 1976). The intermediate collegiate player will be excluded from the study. Then the subjects will be separated into two groups: Morning group and evening group on the basis of said questionnaire. Subjects will receive WBV training either in the morning or in the evening randomly using the chit method. Following 48 hours of wash-out period the subject will be requested to the alternate session than what he has already done.All identifying information on the permission form, as well as demographic data, will be kept strictly confidential.

PROCEDURE:

·       The subjects will be selected on the basis of inclusion and exclusion criteria. They will be asked to fill out the self-reported revised version of Morningness-Eveningness personality questionnaire(MEQ-REV-SR) to assess the chronotype (Terman M et al., 2001;Horne & Ostberg, 1976). Subjects will also be screened to rule out any disease with the help of physical activity readiness questionnaire.

·       Subjects will be given 1-day rest from the game before the WBV training and testing to avoid the training effects. Subjects will be instructed not to perform any form of exercise and not to consume alcohol or coffee 24hr prior to the session, as it will affect the training and testing. A familiarization session will be done for both groups.

·       Before WBV training, both groups will complete a general warmup activity that includes 5 minutes of jogging and active stretching of the major lower limb muscles (2 repetitions of gluteus, quadriceps, hamstring, and calf stretching for 30 seconds).

·       Following a one-minute rest, three trials of baseline measurement of the Y-balance test, %MVIC, CMJ height, 20-m sprint time, and T-test time will be performed.

·       After 5 minutes, subjects will be requested to pick up a chit depending on which they shall be subjected to receive WBV, in the morning or evening.

·       During WBV training, subjects will be required to stand on a WBV platform and be subjected to a vertical sinusoidal mechanical WBV. For 5 minutes, a 30 Hz vibration frequency and a peak-to-peak amplitude 2.5mm of WBV dosage will be delivered. Subjects will receive a single bout of WBV training consisting of two 30-second squatting exercise sets and two 30-second single-leg squatting exercise sets with 30-second rest intervals (Munshi et al., 2022).

·       After giving WBV training, three trials of post-test measurement of the Y-balance, %MVIC through EMG, CMJ height, 20m sprint time, and T-test will be performed, and the best of the three will be recorded.

·       Subjects will be asked to take a 48-hour break to lessen the effects of fatigue on test performance. After 48 hours, the subjects will be swapped to receive intervention.

Then, again, after WBV training, three trials of post-test measurement of Y-balance test, %MVIC CMJ height, 20m sprint time, and T-test will be performed, and the best of the three will be recorded.

Variables

Independent variable

·       Whole body vibration

Dependent variable

·       % MVIC (Maximum voluntary isometric contraction)

·       Countermovement jump height

·       20m sprint time

·       T-test

·       Y balance test