The long-term objective of this research line is to identify and implement an effective and feasible intervention capable of preventing and/or reducing the burden of cardiometabolic and obesity-related diseases that affect Mississippians and others. The pursuit of this long-term objective will begin with achieving the specific aims proposed in this pilot project, which are to determine the effect of single sprint training for improving (1) systemic macro-vascular function, (2) local and systemic micro-vascular function, and (3) cardiorespiratory fitness. These aims will be achieved using a randomized controlled trial whereby 40 males and females will be randomized into an intervention group (n=20) or time-matched negative control group (n=20). The intervention group will perform a single maximal effort sprint on a cycle ergometer for twenty seconds 3 days/week for 4 weeks and the control group will be asked to maintain pre-intervention habits/behavior over 4 weeks. All outcome measures are non-invasive, and will be assessed pre-, mid-, and post-intervention, with the exception of cardiorespiratory fitness, which will be measured pre- and post-. To achieve aim 1, brachial artery flow-mediated dilation via ultrasonography and systolic and diastolic blood pressure via automated oscillometry will be measured on the arm. To achieve aim 2, post-occlusive reactive hyperemia via near-infrared spectroscopy and reactive hyperemia via ultrasound will be measured in the arm and leg, respectively. To achieve aim 3, pulmonary gas exchange will be measured during a graded exercise test on a cycle ergometer. All outcomes will be compared across time between conditions and sex with a three-way Bayesian Repeated Measures ANOVA using pre-values as covariates and an uninformed prior. 95% credible intervals will also be calculated to power future investigations using this intervention. If the intervention is found effective, future studies will be conducted to determine the efficacy of the intervention in larger groups and more clinical populations, and to determine the mechanisms mediating the adaptations. If ineffective, the knowledge gained will be used to develop future interventions.

Inclusion Criteria:

• Age 18-35 years
• Untrained (no regular exercise engagement for the previous 6 months)
• Healthy enough to begin exercise (assessed via Physical Activity Readiness Questionnaire)

Exclusion Criteria:

• Illness/injury preventing cycling exercise
• Prescribed medication to control heart rate
• Prescribed medication to control blood pressure
• Use of nicotine within the previous 6 months

There is no current plan to share individual data outside of the investigators responsible for conducting the study. If data are requested, they will only be shared after being de-identified, unless otherwise required by law.