Supraspinatus Tendon Acute Effects After Two Exercise Exposures: a Crossover Randomized Trial.

Summary

The purpose of this study is to understand acute tendon changes after two exercise programs. We will invite individuals with and without shoulder pain to participate in this study. Every individual will participate in both exercise programs separated by up to 15 days. The researcher will evaluate the shoulder tendon using ultrasound before each exercise program and at 1 hour, 6 hours and 24 hours after each exercise program. The researcher will also evaluate self reported pain, pain sensitivity testing, and self reported questionnaires. We will compare the tendon changes after each exercise program, as well as between participants with and without shoulder pain.

Conditions

• Shoulder Pain
• Healthy Adult

Interventions

BEHAVIORAL

Isotonic exercise program

Participants will perform two isotonic exercises, prone shoulder external rotation and shoulder elevation. The exercises will be performed at a pace of 2-second for both concentric and eccentric phases. For each exercise, participants will perform two sets of 8 repetitions, followed by a third set performed until fatigue. Fatigue will be determined using the Repetition in Reserve Scale, which asks the participant to perform exercises until they reach a self-selected number corresponding to the number of repetitions left that a participant could still complete if needed. We will ask participants to continue the third set until they reach a Repetition in Reserve number of 1. The rest period will be 30 seconds between sets and 2 minutes between exercises. The exercise load will be selected after manual maximal isometric strength testing using a handheld dynamometer. A 40% of the strength testing will be used for exercises in both groups following strength guidelines.

BEHAVIORAL

Plyometric exercise program

Participants will perform two isotonic exercises, prone shoulder external rotation and shoulder elevation. The exercises will be performed at a pace of 1-second for the eccentric phases followed by an explosive concentric phase. For each exercise, participants will perform two sets of 8 repetitions, followed by a third set performed until fatigue. Fatigue will be determined using the Repetition in Reserve Scale, which asks the participant to perform exercises until they reach a self-selected number corresponding to the number of repetitions left that a participant could still complete if needed. Participants will complete the third set until they reach a Repetition in Reserve number of 1. The rest period will be 30 seconds between sets and 2 minutes between exercises. The exercise load will be selected after manual maximal isometric strength testing using a handheld dynamometer. A 40% of the strength testing will be used for exercises in both groups following strength guidelines.

Sponsors & Collaborators

• University of Florida

  lead OTHER

Study Design

Allocation

RANDOMIZED

Purpose

OTHER

Masking

DOUBLE

Model

CROSSOVER

Eligibility

Min Age

18 Years

Max Age

45 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2026-04-20

Primary Completion

2027-04-01

Completion

2027-04-01

Countries

• United States

Study Locations