Improving Blood Pressure and Cardiovascular Risk With Resistance Exercise in African Americans

Overview

After the participant meets all inclusion and exclusion criteria, they will be randomized equally to either the Resistance Training group (RT) or Aerobic Training group (AT). Both groups will participate in an 8 week initial control period, followed by 8 weeks of supervised exercise training, followed by 8 weeks of deconditioning. All participants will undergo the same assessments and procedures one time prior to the initial 8 week control period, and at each of the three periods. Assessments include: blood draws; arterial stiffness testing; ultrasounds of the brachial artery to measure flow-mediated dilation (FMD); gluteal adipose tissue biopsies; exercise testing to determine VO2 max; body composition analysis via DEXA scans; ambulatory blood pressure measurement; diet analysis via food journals; medical history questionnaires; urine analysis for pregnancy; and activity monitoring via accelerometer. Total participation will be 24-26 weeks.

This study is divided into three separate 8-week periods, the Control period, the Exercise Training period and the De-training period. Testing sessions will be done at Week 0, Week 8, Week 16, and Week 24 of the study. Control Period (weeks 0-8): Participants will have a control period of 8 weeks. Participants will be given a brochure regarding the benefits of regular exercise and nutrition on overall health. 1. Baseline visit and eligibility assessment, Week 0: After an initial phone interview to screen participants for eligibility, participants will be scheduled for their two sessions of baseline assessments. Randomization After the subject meets all inclusion and exclusion criteria, the participant will be randomized equally to either the Resistance Training group (RT) or Aerobic Training group (AT) with a table of random numbers by a staff member having no knowledge of the participant's baseline profile. V1A (2 hours): Clinical Research Center and/or Integrative Physiology Lab Participants will report to the UIC CRC or UIC Integrative Physiology Lab after a 12 hour fast. Everyone will be instructed to take all prescribed medications as normal and to continue to drink plenty of water. Participants will also be told not to exercise for 24 hours prior to the testing session. Female participants will be in the follicular stage of their menstrual cycle. After informed consent and a medical history obtained, the following procedures will be performed: * Urine pregnancy test for women * Questionnaires (Health History Questionnaire, Pittsburgh Sleep Quality Index (PSQI), Physical Activity Questionnaire, Automated Self-Administered 24-hour Dietary Assessment Tool (ASA 24), and Alcohol Intake Questionnaire (AIQ) * Anthropometrics: weight, height, waist circumference and BMI * Vitals: Blood pressure and heart rate * Blood draw of approximately 2 tablespoons or 30 mLs * Arterial stiffness test via pulse wave velocity: Sphygmocor (SphygmoCor, AtCor Medical, Sydney, Australia) is a device that used to detect the stiffness of blood vessels. * Ultrasound for brachial flow-mediated dilation with administration of nitroglycerin * Beginning of 24 hour blood pressure monitoring. V1B (2 hours): Integrative Physiology Lab Participants will report to the IPL for the following procedures: * Exercise testing: Maximal oxygen consumption will be evaluated using the treadmill to exhaustion. * Dual Energy X-ray Absorptiometry (DEXA) * Begin 7 days of activity monitoring with accelerometer. V1C (5 minutes): Integrative Physiology Lab Participants will report to the IPL for the following procedures: • Return the accelerometer after 7 days of activity monitoring. Exercise Training Period (weeks 9-16): Participants will participate 3 days a week in either the Resistance Training group (RT) or the Aerobic Training group (AT). 2. Pre-training Testing, Week 8: After the 8 week control period, before training begins, participants will report for two testing visits, and will undergo the following procedures: V2A (2 hours): Clinical Research Center and/or Integrative Physiology Lab: Same as V1A procedures as outlined in the Baseline visit (including the 12 hour fast), with the addition of a subcutaneous gluteal fat biopsy that will be performed in conjunction with the above measures, or scheduled separately at the Clinical Research Center. V2B (2 hours): Integrative Physiology Lab: Participants will report to the IPL for the same procedures as outlined in the Baseline visit (V1B). V2C (5 minutes): Integrative Physiology Lab: Participants will report to the IPL for the same procedures as outlined in the Baseline visit (V1C). Exercise Intervention Groups: Aerobic Training Intervention (weeks 9-16): Subjects will undergo a supervised endurance training program in accordance with established guidelines. Resistance Training Intervention (weeks 9-16): Subjects randomized to 8-week resistance exercise training program will visit the UIC Integrative Physiology exercise research laboratory 3 times per week, 45 min per session. 3. Post training Testing, Week 16: The two visit post-training testing will start 24-48 hours after last exercise session to avoid potential effects of the acute exercise bout. This testing is identical to the testing that occurred at the beginning of the exercise training period (V2) at Week 8. Participants will report for two testing visits, and will undergo the following procedures: V3A (2 hours): Clinical Research Center and/or Integrative Physiology Lab: Same V2A procedures as outlined in the Pre-Training visit (V2A) (including the 12 hour fast). V3B (2 hours): Integrative Physiology Lab: Participants will report to the IPL for the same procedures as outlined in the Pre-Training visit (V2B). V3C (5 minutes): Integrative Physiology Lab Participants will report to the IPL for the same procedures as outlined in the Pre-Training visit (V2C). De-Training Follow-up (weeks 16- 24): All subjects will be asked to resume normal activities after the 8-week exercise training program. 4. Post-Detraining Testing, Week 24: All of the procedures described in Post-Training visits will be repeated. Participants will report for two testing visits, and will undergo the following procedures: V4A (2 hours): Clinical Research Center and/or Integrative Physiology Lab: Same V2A procedures as outlined in the Pre-Training visit (V2A) (including the 12 hour fast). V4B (2 hours): Integrative Physiology Lab: Participants will report to the IPL for the same procedures as outlined in the Pre-Training visit (V2B). V4C (5 minutes): Integrative Physiology Lab Participants will report to the IPL for the same procedures as outlined in the Pre-Training visit (V2C).