The Influence of Oral Contraceptives During Disuse

The Effects of Oral Contraceptive Use on Grip Strength and Neuromuscular Activation During Short-Term Immobilization of the Wrist/Hand

Studies across various sports and physical activities have consistently shown that females incur more injuries compared to their male counterparts, but the underlying reasons for this disparity remain poorly understood. While differences in hormone levels between males and females have been speculated to play a role, very little rigorous research has been conducted to directly examine potential connections between sex hormones and injury risk. Specifically, females have been shown to be at greater risk for hand and wrist injuries. The higher injury incidence begins at puberty and persists across the lifespan, suggesting a link to hormonal factors. However, significant gaps remain in understanding the relationships between the menstrual cycle, exogenous hormones from birth control, and risk factors for sports-related injury in females. The purpose of this study is to examine changes in muscle strength and neuromuscular activation among females using monophasic oral contraceptives, females not using oral contraceptives, and males during one week of wrist/hand immobilization.

Study Overview

• Status: Recruiting
• Conditions: Rehabilitation; Physical Therapy; Menstrual Cycle; Oral Contraceptives
• Intervention / Treatment: Other: Wrist/hand immobilization

• Study Type: Interventional
• Enrollment (Estimated): 60
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Matt S Stock, Ph.D.; Phone Number: 407-823-0364; Email: matt.stock@ucf.edu
• Study Contact Backup: Name: Randi Richardson, DPT; Phone Number: 407-823-0377; Email: Randi.Richardson@ucf.edu

Study Locations

• United States
  • Florida
    • Orlando, Florida, United States, 32816
      • Recruiting
      • University of Central Florida
      • Contact: Matt S Stock, Ph.D.; Phone Number: 407-823-0364; Email: matt.stock@ucf.edu
      • Principal Investigator: Matt S Stock, Ph.D.

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Right handed males and females
• Ages 18-35 years
• For females, consistent use of monophasic oral contraceptives for the previous 6 months OR having completely refrained from contraceptives for the previous 6 months.

Exclusion Criteria:

• Gender identity inconsistent with biological sex (due to the influence that drugs used for gender reassignment may have)
• Females that are amenorrheic (lack of menstruation for ≥3 consecutive cycles) or oligomenorrheic (menstrual cycle length ≤36 days)
• Menstrual cycle irregularities among females not using oral contraceptives (regularity defined as every 21 to 35 days and/or at least 5 periods in the last six months)
• Any contraceptive use other than monophasic oral contraceptives within the last 6 months
• Monophasic oral contraceptives that has been inconsistent over the previous 6 months
• Score of greater than 2/5 on question 9, or a score of greater than 1/5 on question 10 or 11 on the quick Disabilities of the Arm, Shoulder and Hand outcome measure indicating pain/discomfort of the upper extremities (shoulder, elbow, wrist, hand)
• Dominant hand is the left hand
• Body Mass Index less than 18.5 kg/m2 or greater than 29.9 kg/m2
• Current depression or anxiety
• History of musculoskeletal injury, pain, or surgery of the elbow, wrist, or hand
• Unwillingness to avoid upper-body exercise during Phase 1
• Unwillingness to avoid exercise and alcohol 24 hours prior to each testing visit.
• Neuromuscular disease (e.g., Multiple Sclerosis, amyotrophic lateral sclerosis, Parkinson's)
• Metabolic disease (e.g., diabetes, thyroid disorder, metabolic syndrome)
• Personal or family history of blood clots
• Trouble using or controlling muscles
• History of cancer
• History of stroke
• History of heart attack
• History of arthritis
• Allergy to rubbing alcohol
• Lack of transportation to and from the laboratory
• Current or planned pregnancy (within the next three months)
• Implant of any kind
• The use of medications that may increase the risk of blood clots (i.e., corticosteroids such as prednisone, testosterone and anabolic steroids, selective estrogen receptor modulators like tamoxifen, aromatase inhibitors including anastrozole, thalidomide and lenalidomide, erythropoiesis-stimulating agents such as epoetin alfa, antipsychotics like chlorpromazine, antidepressants including paroxetine, various cancer chemotherapies, immune modulating drugs, antivirals such as ritonavir, and tamoxifen).
• The use of creatine monohydrate and beta alanine supplementation within the previous 6 months.
• The use of any medication or supplement that could influence hormone levels within the previous 6 months.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Wrist/hand immobilization; Participants will have their wrist and hand immobilized using a rigid splint continuously for 7 days. The splint will restrict all wrist and hand movement and must be worn at all times for the full 7 day period, and may only be removed under supervision of the research participants.	Other: Wrist/hand immobilization; Study participants will have their left wrist/hand immobilized with a splint for 7 days. The splint will be worn 24 hours per day.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Grip Strength	Maximal force (N) will be measured during a grip strength test	Grip strength will be tested weekly for at least 3 weeks (i.e., baseline, post-immobilization, post 1 week recovery). Testing will continue every week following immobilization until grip strength has returned to baseline levels.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Muscle activation	Surface electromyographic amplitude of hand and wrist muscles will be measured during the maximal grip tests.	Grip strength will be tested weekly for at least 3 weeks (i.e., baseline, post-immobilization, post 1 week recovery). Testing will continue every week following immobilization until grip strength has returned to baseline levels.

Collaborators and Investigators

• Sponsor: University of Central Florida

Study record dates

Study Major Dates

• Study Start (Actual): January 26, 2024
• Primary Completion (Estimated): December 1, 2024
• Study Completion (Estimated): May 1, 2025

Study Registration Dates

• First Submitted: February 9, 2024
• First Submitted That Met QC Criteria: February 16, 2024
• First Posted (Actual): February 23, 2024

Study Record Updates

• Last Update Posted (Actual): February 23, 2024
• Last Update Submitted That Met QC Criteria: February 16, 2024
• Last Verified: February 1, 2024

More Information

Terms related to this study

• Keywords: menstrual cycle; rehabilitation; oral contraceptives; immobilization; weakness
• Other Study ID Numbers: STUDY00006302

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: We plan to make de-identified individual participant data (IPD) from this study available to other researchers once the primary analysis is completed and the study results have been published. The data will be shared in a manner that protects participant confidentiality and adheres to applicable laws and regulations.
• IPD Sharing Time Frame: IPD will be made available beginning 1 year after the study completion date.
• IPD Sharing Access Criteria: Researchers must submit a methodologically sound proposal outlining their planned analysis of the data. Proposals will be reviewed and approved by an independent panel appointed by the Principal Investigator. Requests should be sent to matt.stock@ucf.edu
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; ICF

Drug and device information, study documents

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