Effects of Concurrent Training on Blood Lipids and Glucose

Abstract

Aerobic exercise helps lower LDL-cholesterol and triglycerides, and in turn raises HDL-cholesterol. Research on the effects of resistance training on lipid levels has demonstrated no changes. PURPOSE: This study investigated the effects of 12 weeks of concurrent training on blood lipid and glucose levels in untrained college-age males. Concurrent training includes both cardiovascular and resistance training completed within the same training time period. METHODS: Six males (mean age 19.5±1.5 y, weight 84.76±21.01 kg, height 181.82±5.22 cm) and one control male (age 21, weight 80.82 kg, height 184.15 cm) participated in this pilot study. After providing informed consent, subjects were tested in VO2 max, body composition through bioelectrical impedance, arm and leg circumferences, 3 repetition maximum (RM) bench and squat, and the YMCA bench endurance test. Subjects also had fasting blood drawn to test for total cholesterol, HDL and LDL cholesterol, triglycerides, and glucose at week 0, 6, and 12 of the study. Subjects participated in concurrent training for 12 weeks, 3 days per week. Subjects completed 8-10 resistance training exercises first, and then completed their hour of training by walking/jogging/running for up to 30 minutes on a treadmill at a prescribed target heart rate. After 12 weeks, subjects were post tested with the same tests as before. RESULTS: Physiological measures were analyzed using a Student's T-test, where blood data was analyzed using ANOVA. Significance was set at p<0.05. The only significant changes post training were an increase in 3 RM squat strength (p=0.04) and a decrease in blood glucose from week 0 to week 12 (p=0.04). DISCUSSION: After training, subjects improved their fitness level slightly, although only significantly (p=0.04) in the 3 RM squat measurement. This amount of improvement is expected in concurrent training. Although lipid levels declined, there was a large standard deviation seen and no significant differences noted. There was a significant decline in glucose levels (p=0.04) from week 0 to week 12. CONCLUSION: These results are promising for a pilot study. Using more subjects, utilizing a longer training period, and including subjects with abnormal lipid levels may make it more likely to find statically significant differences in future studies.