Different modes of exercise have been shown to reduce the health risks associated with elevated plasma Cholesterol (Tjonna, Lee et al. 2008) (Martins, Verissimo et al. 2010). However the results do not agree on the modes of exercise that are beneficial. Some recent research, the STRRIDE clinical study, has shown little Cholesterol reduction (Bateman, Slentz et al. 2011). The mode of high-intensity, short-duration, resistance exercise has not been compared with the Government recommendations of moderate-intensity exercise. PURPOSE: To compare changes in Total Cholesterol and in HDL over 3 months in moderate-intensity rhythmic exercisers and high-intensity resistance exercisers. METHODS: 63 participants in a health club setting gave voluntary informed consent and completed 3 months of supervised exercise, divided between 30-minute bouts of moderate-intensity rhythmic exercise 3 to 5 times a week (MI), 8 minute bouts of high-intensity resistance exercise only 1 to 2 times a week (HI) and a no additional physical activity control group (CON). Venous blood samples (12 hour prior fast) were taken before and after the 3 months. Total Cholesterol and HDL were determined using an automated photometric chemistry analyser. RESULTS: The mean reductions in the Total Cholesterol / HDL ratio (+/- standard error) over the 3 months for the groups were: MI (n=18) 0.11 +/- 0.16, HI (n=23) 0.26 +/- 0.11 and CON (n=22) -0.04 +/- 0.09. However, as can be seen in plots, the MI exercise was more beneficial than this data indicates. Although the Cholesterol/HDL ratios were balanced between the 3 starting groups, uneven attrition has distorted the results. CONCLUSION: These results show that, over a 3-month period, 30-minute bouts of moderate-intensity rhythmic exercise and short bouts of high-intensity resistance exercise both reduce the Cholesterol/HDL ratio. Further research, in which the total work done is controlled, is now required to see if it is the mode or intensity of the exercise that has the greatest effect. Plus greater participant numbers are required for this reported research to strengthen the statistics.