Effects of Stretching on Strength of Proximal and Distal Group of Muscles - A Comparative Study

Muscular flexibility is believed to prevent injuries and improve movement therefore most coaches include stretching exercises in their pre-competition and pre-exercise warm-up routines. One question arises here, should sports persons avoid stretching exercises prior to sporting events thereby exposing themselves to musculoskeletal injuries, or should they continue stretching exercises prior to sporting events and risk losing the maximal performance? The aim of this study is to compare the effects of 2, 4, and 8 min of static stretching (SS) on isometric maximum voluntary contraction (MVCF) force between proximal (Hamstrings) and distal group (Calf) of muscles.

Study Overview

• Status: Completed
• Conditions: STRETCHING
• Intervention / Treatment: Other: Muscle static stretching

Detailed Description

OBJECTIVE: To compare the effects of 2, 4, and 8 min of static stretching (SS) on isometric maximum voluntary contraction (MVCF) force between proximal (Hamstrings) and distal group (Calf) of muscles.

DESIGN: Two-group pretest-posttest experimental design. METHODS: Each subject visited the Rehabilitation center on three days: On day-I for static stretching for 2 minutes (SS2), day-II for 4 minutes (SS4), and day-III for 8 minutes (SS8). Isometric Maximum Voluntary Contraction Force (MVCF) measurement was done prior (Pre), 0-min, 10-min, and 20-min post-intervention (i.e. stretching). Each visit was separated by a gap of at least 3-4 days. On each visit, each subject underwent (a). Pre-intervention evaluation, (b). Intervention, (c). Post-intervention evaluation. Subjects performed stretching exercises under the supervision of expert Physical Therapist. The outcome assessor who was kept blind to study protocol did all measurements.

• Study Type: Interventional
• Enrollment (Actual): 28
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Saudi Arabia
  • Riyadh, Saudi Arabia, 11433
    • King Saud University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 22 years to 30 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

For group A: subjects performed active knee extension test and those lacking at least 20 degrees of active knee extension range, with hip in 90 degree of flexion were selected. For group B (Calf): Subjects performed active foot dorsiflexion in long sitting position with back supported against the wall and those having not more than 20-degree range of motion were selected.

Selected subjects used to engage in 1-5 hours of regular physical activity per week (recreationally active) that does not involve stretching exercise

Exclusion Criteria:

Subjects reporting any current or ongoing neuromuscular disease, injury specific to lower limb joints, any apparent limit in knee or ankle ROM and competitive/professional athletes were excluded from study.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Group A (Hamstrings); Hamstring stretching would be done then isometric strength would be measured.	Other: Muscle static stretching; On day-I: Static Stretching done for 2 minutes (SS2), on day-II: Static Stretching done for 4 minutes (SS4), and on day-III: Static Stretching done for 8 minutes (SS8).
Experimental: Group B (Calf); Calf stretching would be done then isometric strength would be measured.	Other: Muscle static stretching; On day-I: Static Stretching done for 2 minutes (SS2), on day-II: Static Stretching done for 4 minutes (SS4), and on day-III: Static Stretching done for 8 minutes (SS8).

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in isometric maximum voluntary contraction force before and after stretching	Change in isometric muscle strength measured before and after stretching using strain gauge on 3 different days	MVCF was measured immediately (0 min), 10-min and 20 min post intervention on 3 different days, with each day separated by gap of 3-4 days.

Collaborators and Investigators

• Sponsor: King Saud University

Publications and helpful links

General Publications

• Alghadir AH, Khan M, Quddus N, Chawla C. Effects of different stretch durations on the strength of the proximal and distal group of muscles - a randomized trial. Medicine (Baltimore). 2022 Oct 28;101(43):e31279. doi: 10.1097/MD.0000000000031279.

Study record dates

Study Major Dates

• Study Start (Actual): January 23, 2019
• Primary Completion (Actual): July 17, 2019
• Study Completion (Actual): September 5, 2019

Study Registration Dates

• First Submitted: June 24, 2020
• First Submitted That Met QC Criteria: June 28, 2020
• First Posted (Actual): July 1, 2020

Study Record Updates

• Last Update Posted (Actual): July 1, 2020
• Last Update Submitted That Met QC Criteria: June 28, 2020
• Last Verified: June 1, 2020

More Information

Terms related to this study

• Keywords: Muscle strength; muscle stretching exercises; strain gauge
• Other Study ID Numbers: RRC-2019-06

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No