EFFECTS OF SIMULATED RAPID WEIGHT GAIN ON CARDIOVASCULAR MEASURES
Rapid weight gain during college may cause an increased demand on the cardiovascular system, predisposing young adults to further complications as they age. Studies have shown that the average weight gain during the first 2 years of college is 6% of body weight. While we know that weight gain increases sedentary behavior, and vise versa, we don’t know how a 6% increase in body weight effects the cardiovascular system. The purpose of this study was to determine how simulated rapid weight gain affects cardiovascular function in a college-aged population. METHODS: Ten participants, including 6 males and 4 females, between the ages of 20-48y (mean 25.4 + 8.4y, 73.8 + 11.9kg, 175.4 + 6.1cm) completed the study. All subjects were considered low risk (ACSM), and provided written consent. Resting heart rate, blood pressure, height and weight were measured prior to testing. Participants performed two 3-minute step tests using a 12-inch platform, to a step cadence of 96 bpm, separated by a 15-minute rest. One test was performed with just body weight, and one was performed with an additional 6% of body weight worn in a weighted belt or vest (mean additional weight 4.4 + 0.7kg). Starting condition was randomly selected. An indirect calorimeter measured VO2 and heart rate during each step test. Immediately after each step test, systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured and recovery heart rate (HR) was measured for a full minute. Differences in post exercise HR, SBP, and DBP were analyzed using dependent t-tests at p< 0.05. RESULTS: There was no significant difference in absolute VO2 (1.87 + 4.05 L/min vs 2.0 + 3.28 L/min), recovery HR (80.80 + 14.79 bpm vs 90.30 + 22.93 bpm), SBP (148.5 + 15.1 mmHg vs 149.4 + 12.3 mmHg) or DBP (90.3 + 6.9 mmHg vs 87.0 + 8.1 mmHg), between the body weight and weighted step tests, respectively (p>0.05). CONCLUSION: These results showed there was no statistical difference in the measured cardiovascular components following a short cardiovascular challenge as a result of additional weight. Although there was a strong trend for additional weight to produce higher recovery heart rate (p=0.054) and absolute VO2 during the exercise (p=0.074), it may be that 6% additional weight is below the threshold required to produce a significant challenge to the cardiovascular system, or that low statistical power affected our results. We did not stratify or control for fitness level so it could also be that our relatively active sample could handle the additional load. Future studies should use a longer exercise bout and determine a dose-response relationship between added weight and cardiovascular changes and stratify for fitness level.
Holmes, M.; Caldwell, K.; Cutting, H.; Estrada, J.; and Witzke, FACSM, K.
"EFFECTS OF SIMULATED RAPID WEIGHT GAIN ON CARDIOVASCULAR MEASURES,"
International Journal of Exercise Science: Conference Proceedings: Vol. 8
, Article 47.
Available at: https://digitalcommons.wku.edu/ijesab/vol8/iss5/47