Medicine and Health Sciences Commons^™

Case Studies In Physiology: Male To Female Transgender Swimmer In College Athletics, Jonathon Senefeld, Sandra K. Hunter, Doriane Coleman, Michael J. Joyner

Exercise Science Faculty Research and Publications

There is current scientific and legal controversy about sports competition eligibility regulations for transgender athletes. In this case study, we quantified performances by an elite, transgender woman (male sex, female gender identity) college swimmer who competed in both the men’s and women’s National Collegiate Athletic Association (NCAA) categories. We also contextualized her performances with respect to world-record performances and contemporary elite college swimmers. These data demonstrate that the declines in freestyle swimming performances of a transgender woman after about 2 yr of reported feminizing gender-affirming hormone treatment (0.5% for the 100 to 7.3% for the 1,650 yard distance) are smaller …

Muscle Function And Fatigability Of Trunk Flexors In Males And Females, Rita Deering, Jonathon Senefeld, Tatyana Pashibin, Donald A. Neumann, Sandra K. Hunter

Exercise Science Faculty Research and Publications

Background

Optimal function of the abdominal muscles is necessary for several life functions including lifting and carrying tasks. Sex differences in strength and fatigability are established for many limb muscles and back extensor muscles, but it is unknown if sex differences exist for the abdominal muscles despite their functional importance.

Methods

Eighteen females (24.3 ± 4.8 years) and 15 males (24.1 ± 6.6 years) performed (1) isometric trunk flexion maximal voluntary contractions (MVCs) in a range of trunk positions to establish a torque-angle curve and (2) submaximal (50% MVC), intermittent isometric contraction (6 s on, 4 s off) until task …

Mechanisms Of Fatigue Differ After Low- And High-Force Fatiguing Contractions In Men And Women, Tejin Yoon, Bonnie A. Schlinder-Delap, Erin E. Griffith, Sandra K. Hunter

Exercise Science Faculty Research and Publications

The magnitude of failure in voluntary drive after fatiguing contractions of different intensities in men and women is not known. The purpose of this study was to compare the time to task failure and voluntary activation of men and women for a sustained isometric contraction performed at a low and high intensity with the elbow flexor muscles. Nine men and nine women sustained an isometric contraction at 20% and 80% of maximal voluntary contraction (MVC) force until task failure during separate sessions. The men had a shorter time to failure than women for the 20% but not the 80% MVC …