Exploring the Modulatory Role of Sex Hormones Along the Neuromechanical Axis in Females (EMRSHN)

The University of Texas System (UT)

Status: Completed

Conditions: Role of Sex Hormones Along the Neuromechanical Axis

Treatments: Device: Transcranial Magnetic Stimulation Device

Study type: Observational

Funder types: Other; NIH

Identifiers

NCT03947684

1R01AR069176-01A1 (U.S. NIH Grant/Contract)

STU-2018-0192

Details and patient eligibility

About

The goal of this project is to test our central hypothesis that changes in sex hormone concentration result in changes to the basic elements of motor control - at multiple levels, from the musculotendinous unit to motor control circuitry. Under Aim 1 the investigator will determine the influence of sex hormone fluctuations on the muscle stretch reflex during active and passive states, and the time lag between hormone concentration changes and the reflex response. The investigator will use a technically simple assessment that could be implemented in the field. Under Aim 2 the investigator will determine the influence of sex hormone fluctuations on spinal motor neuron excitability using H-reflex as a probe and the simultaneous change in the muscle mechanics using muscle twitch response. Aims 1 & 2 will include a focus on the differential role of oral contraceptives. In Aim 3 the investigator will use paired-pulse transcranial magnetic stimulation during active contraction to determine the influence of sex hormone fluctuation.

Enrollment: 102 patients

Sex: All

Ages: 18 to 39 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Females: ages 18-39 years, who are eumenorrheic (regular monthly cycles of 24-35 days) or on a stable hormonal contraceptive regimen for 6 months (oral, transdermal or vaginal), no history of pregnancy, moderately active (less than 7 hours of vigorous physical activity per week)
• Males: Ages 18-39

Exclusion criteria

• History of musculoskeletal or orthopedic injury of the spine, hip, knee, ankle or foot, history of neurological injury of the peripheral or central nervous system, current smoker, history of disordered eating, history of stress fracture in the lower limb, history of a connective tissue disorder (Marfan's syndrome, Ehlers-Danlos disease).
• For female participants only: Point of care screening for anemia will be completed, and individuals with hemoglobin levels <11.6 g/dl will be excluded from participating in the study.
• Specific exclusion criteria for TMS (male and female): pacemaker, metal implants in the head region, history of epilepsy or seizures, skull fractures or skull deficits, concussion within the last 6 months, unexplained recurring headaches, medications that lower seizure threshold, and pregnancy.
• Additional exclusion criteria for female participants: History of menstrual dysfunction (primary or secondary amenorrhea, oligomenorrhea, anovulatory cycles, polycystic ovarian disease), current or past pregnancy, started or stopped taking oral contraceptives within the previous 6 months, exercise vigorously more than 7 hours per week or currently participating in competitive level sports. The reason for excluding highly active or competitive athletes is due to the high rate of undiagnosed menstrual dysfunction in females of this population.
• This study will not include: adults unable to consent, Individuals who are not yet adults (infants, children, teenagers), pregnant women or prisoners.

Trial design

102 participants in 3 patient groups

Non-Oral Contraceptive (NOC)

Description:

Females ages 18-39 years, who are eumenorrheic (regular monthly cycles of 24-35 days) and moderately active. Exclusion criteria: History of musculoskeletal or orthopedic injury of the spine, hip, knee, ankle or foot, history of neurological injury of the peripheral or central nervous system, history of disordered eating, of a connective tissue disorder (Marfan's syndrome, Ehlers-Danlos disease), history of or current diabetes, pacemaker, metal implants in the head region, history of epilepsy or seizures, skull fractures or skull deficits, concussion within the last 6 months, unexplained recurring headaches, medications that lower seizure threshold, and pregnancy.

Oral Contraceptive ( OC)

Description:

Females: ages 18-39 years, who are on a stable hormonal contraceptive regimen for 6 months (oral, transdermal or vaginal) and moderately active. Exclusion criteria: History of musculoskeletal or orthopedic injury of the spine, hip, knee, ankle or foot, history of neurological injury of the peripheral or central nervous system, history of disordered eating, of a connective tissue disorder (Marfan's syndrome, Ehlers-Danlos disease), history of or current diabetes, started or stopped taking oral contraceptives within the previous 6 months, participate in high impact endurance training (i.e. pre-marathon training, body building), or currently participating in competitive level sports.

Male

Description:

Males: Ages 18-39. Exclusion criteria: History of musculoskeletal or orthopedic injury of the spine, hip, knee, ankle or foot, history of neurological injury of the peripheral or central nervous system, history of disordered eating, of a connective tissue disorder (Marfan's syndrome, Ehlers-Danlos disease), history of or current diabetes, pacemaker, metal implants in the head region, history of epilepsy or seizures, skull fractures or skull deficits, concussion within the last 6 months, unexplained recurring headaches, and medications that lower seizure threshold.