Reflection paper

The overall effect of exercise on HDL, LDL, total cholesterol and total triglyceride profiles can be better solidified by analyzing the effect of various exercise intensities in combination of energy output rather than just the overall effect of exercise on those four functional properties. It should be understood that the production of lipids vary in response upon the duration of exercise, therefore influencing the relationship between C-reactive proteins and blood lipids. In order to calculate a more accurate analysis, blood lipid measurements should be taken at different maximum oxygen consumption sessions and intensities. In 2012, Tsao conducted a study that analyzed the effects of different exercise intensities comparable to C-reactive proteins and blood lipid levels. In the Tsao’s research it was found that LDL, total cholesterol and total triglyceride profiles had not changed with the influence of exercise intensity.3 On the contrary, as the maximum oxygen consumption increased from 25% to 65% to 85% during the exercise sessions, the HDL levels simultaneously increased from -0.42 HDL to -0.13 HDL to 0.23 HDL levels.3

According to a study conducted by Chaudhary in 2011, it can be stated that both aerobic exercise and resistance training influence the effect on HDL-C in the blood, thus perpetuating an effect on LDL-C in the blood. For the HDL cholesterol to increase, aerobic training (especially low intensity aerobic training) is first performed.1 The elevation of HDL cholesterol can then be inversely related to the risk of coronary heart disease in the participating individual due to the transportation HDL conducts. 1 As aerobic training continues, the triglyceride concentration decreases, therefore increasing the utilization of free fatty acids in the body.1 Subsequently through this process, the levels of low-density lipoprotein cholesterol (LDL-C) decreases.1

The previous studies conducted by Tsao (2012) and Chaudhary (2012) focused on the effects of sporadic training on HDL-C levels. In comparison to the previous studies, the Musa (2009) study showed a difference in their study by increasing the duration of the work-rest interval intertwined with the eight week high-intensity exercise program conducted on untrained young adult me. The intention of the Musa (2009) study was to raise the subject’s HDL-C levels while simultaneously decreasing the total cholesterol levels and the atherogenic index (TC/HDL-C).2 If this study could prove the researcher’s hypothesis, then one could propose alternative exercise methods that would further reduce the risk of cardiovascular disease.2

After the Musa (2009) study had concluded, it was found that there were no changes in total cholesterol levels in regards to the subjects that had been tested. Due to the fact that all of the tested subjects had entered the study with favorable pre-training mean total cholesterol levels, it can be assumed that there was no opportunity for the total cholesterol levels to further reduce.2 Therefore, this study cannot be perpetuated for proper use in a general population.

The Musa (2009) study discovered two different findings between the participants of the control group and the experimental group. Post testing, the experimental group showed an increase in HDL-C levels as well as a decrease in the atherogenic index (TC/HDL-C) and the distance run times.2 On the contrary, the participants in the control group showed no change in any of the four variables (HDL-C, atherogenic index, TC and distance run times).2

The literature presented by the Musa (2009) study suggested an increase in HDL-C levels when adding endurance training and/or high-intensity aerobic exercise into the lives of young untrained men.2 For the purpose of continually improving the HDL-C levels and the atherogenic index for trained individuals, a longer duration of continuous high-intensity interval training should be implemented.2 Therefore, by taking a serious approach and participating in high-intensity interval training, young adult men (with favorable TC levels) can significantly reduce their risk for cardiovascular disease by 18-27% when increasing their HDL-C levels and another 37% by decreasing their atherogenic index.2

References

1 Chaudhary, S., Kang, M. K., & Sandhu, J. S. (2011). The Effects of Aerobic Versus Resistance Training on Cardiovascular Fitness in Obese Sedentary Females. Asian Journal of Sports Medicine, 1, 177-184.

2 Musa, D. I., Adeniran, S. A., Dikko, A. U., & Sayers, S. P. (2009). The Effect of A High-intensity Interval Training Program on High-Density Lipoprotein Cholesterol in Young Men. Columbia, MI: National Strength and Conditioning Association.

3 Tsao, T. H., Yang C. B. & Hsu C. H. (2012). Effects of Different Exercise Intensities With Isoenergetic Expenditures on C-Reactive Protein and Blood Lipid Levels. Research Quarterly for Exercise and Sport , 81, 293-299.