The objective of the study is to use neurological techniques to obtain quantitative measurements of nervous system control of skeletal muscle activity in adults aged 60-85 who are either long-term resistance exercisers or who are untrained.

We propose to perform a cross-sectional study in 20-40 highly resistance-trained people and compare with 20-40 untrained people matched for age, sex, and BMI. in adults.

Participant will complete 5 study visits. In the first visit, participants will complete a screening visit in which blood will be taken to rule out inclusion and exclusion criteria. Participants will also have their body composition measured by DEXA, Meal tolerance testing, a VO2max test on a cycle ergometer, and a muscle strength test using a knee extension machine, handgrip dynamometer and muscle motion testing.

A second and third visit will be needed for meal tolerance testing will be completed and MRI of the brain.

In the fourth and fifth visits, we will use transcranial magnetic stimulation (TMS) with electromyography (EMG) to track changes in in skeletal muscle excitability following cortical stimulation.

In the third visit, TMS-EMG measurements will be repeated to access measurement reproducibility.

Inclusion Criteria

• Participant must have a BMI between 18.5 and 38
• Participant be aged between 60 and 85
• Regularly exercises at least 5 days a week a minimum of 30 minutes per day.
• Engages in less than 2 days of exercise less than 30 minutes each day.
• Participant must use the Mayo Clinic patient online portal.
• Participant must be able to understand English without the need of an interpreter.
• Must be willing to be contacted for research
• Participant must be willing and capable to provide consent.
• Participants shall be generally healthy as deemed acceptable by the principal investigator
• Men and women will be participant in this study. Women cannot be pregnant during this study.

Exclusion Criteria:

• Surgical History - Gastric surgery, pacemaker placement, weight loss surgery, metabolic and obstetric surgery.
• Smokers will be excluded from the study.
• Medications: Insulins, common diabetic drugs, anti-hyperglycemic drugs, beta blockers cardiac selective, beta-blockers noncardiac selective, oral steroids, opioids anti-depressants, and hormones
• Conidiations and Diagnosis: Disorder of coronary artery, hepatic failure, gastroparesis, disorder of the adrenal gland, drug related disorders, substance abuse, malignant neoplastic disease, psychotic disorders, disorder of skeletal muscle, finding of brain, chronic kidney disease, renal failure syndrome, disorder of pulmonary circulation, cerebrovascular disease, neuro developmental disorder, disorder of immune function, disorder of central nervous system.
• Participants are not to have an abnormal value as part of a lipid panel within the past 6 months.
• Participant will be excluded if they have recreational drug use or a history of alcohol abuse
• Inability or unwillingness of individual or legal guardian/representative to give written informed consent.
• Current or past participation within a specified timeframe in another clinical trial, as warranted by the administration of this intervention.
• Participant will be excluded if they have epilepsy.
• Participant will be excluded if they have cranial metal/device implants
• Participant will be excluded if they are pregnant

A total of 80 participants will be equally divided into resistance-trained and untrained groups. Participants will be matched for age, sex, and BMI. Participants are to have a fasting blood sugar under 140 mg/dL. Untrained men and women will have a hip to waist ratio of >0.85 in women or >80cm and >0.90 in men or >94cm. Participants will be from the Rochester Minnesota area aged 60-85 with a BMI 30-38.