Lunelle

Non-combat-related muscle, tendon and bone injuries are the most common injuries suffered by military personnel, particularly in new recruits. These injuries impact military readiness and are responsible for roughly 60% of limited duty days, 65% of soldiers who are unable to deploy, and nearly $500 million in medical cost to the government annually in the Army alone. Drug interventions must be studied and developed to prevent these negative outcomes and prepare military personnel for the demands of military service. At the current time, military leadership has identified critical gaps in understanding how to minimize these injuries and train soldiers with drug intervention serving among those gaps. The goal of this study is to determine how a hormonal intervention can change muscle, tendon, and bone function as well as physical and psychological performance in response to mental and physical stress. To do so, we will examine sex hormone (testosterone, estrogen) levels, muscle, tendon, and bone images, blood samples, and physical and mental performance. We will look at things like changes in hormone levels, chemicals released from active skeletal muscles, and your body composition. The results from this study will be used to improve physical readiness training in the military with the goal of reducing injuries.

The menopause transition is associated with a decrease in artery health and an increased risk for weight gain in storing fat in the stomach area which may increase the risk for heart disease. The purpose of this research is to study how the decrease in estrogen at menopause changes artery health and fat gain, and risk of disease in women as they age. The first aim in this study will determine whether short term and long term low estrogen levels in premenopausal women decreases artery function and whether this is related to an increase in fat in the stomach area. The second aim will determine whether the changes in artery health and body fat are related to changes in a pathway that breaks down an important amino acid called tryptophan. This pathway is thought to play a role in regulating the aging process. Therefore, the investigators will determine whether the decrease in artery health and the increase in body fat in the stomach region with low estrogen is related to changes in this pathway in the blood, in vascular cells and fat tissue. Because estrogen levels fluctuate in premenopausal women, the investigators will use an approach (intervention) that controls estrogen levels to address these aims. The investigators will use a medication that is typically used to treat endometriosis or uterine fibroids to lower estrogen levels and an estrogen patch to increase estrogen in some women. Some women will receive a patch that has no estrogen (called a placebo patch). The intervention period will be 20 weeks. The study will provide us with new knowledge on how low estrogen with menopause affects artery health and fat gain estrogen.

This trial tests if giving testosterone to men with low levels can help them recover better from major urologic surgery by making them stronger and healthier. Testosterone therapy has been studied extensively and shown to improve various health outcomes in men with low testosterone levels, including muscle mass, bone density, libido, stamina, and cognition.

This pilot study will determine the feasibility of implementing a combinatory rehabilitation strategy involving testosterone replacement therapy (TRT) with locomotor training (LT; walking on a treadmill with assistance and overground walking) in men with testosterone deficiency and walking dysfunction after incomplete or complete spinal cord injury. The investigators hypothesize that LT+TRT treatment will improve muscle size and bone mineral density in men with low T and ambulatory dysfunction after incomplete or complete SCI, along with muscle fundtion and walking recovery in men with T low and ambulatory dysfunction ater incomplete SCI.