PURPOSE: The purpose of this study was to examine the impact of time spent in moderate or vigorous intensity physical activity (PA) on blood lipids, after controlling for total PA in an older adult population. METHODS: Data were collected on 89 older adults (30 males, 59 females; 64.8 ± 8.1 y; 31.5 ±9.7 % body fat). Measures of body height, mass, 3-compartment body composition using dual-energy x-ray absorptiometry were collected. A fasting blood sample was analyzed for total cholesterol (TC), HDL-C, LDL-C, and triglycerides (TRIG). Participants were then asked to wear an accelerometer (Actigraph 7164, Fort Walton Beach, FL) during all waking hours for seven consecutive days. Total time spent in moderate intensity PA (MPA) and vigorous intensity PA (VPA) was calculated with the Freedson et al. (1998) equation. Total PA level was determined from average total accelerometer counts/d. Hierarchical multiple regression analyses were completed to determine the impact of time spent in MPA or VPA while controlling for age, gender, % BF and total PA on TC, HDL-C, LDL-C and TRIG. RESULTS: This group of older adults had borderline high TC (202.6 ± 40.7 mg/dL), normal TRIG (111.6 ±66.0 mg/dL), high HDL-C (62 ± 19.3 mg/dL), and near optimal/ above optimal LDL-C (112 ± 33.3 mg/dL). Participants spent an average of 32.6 ± 24.6 minutes in MPA (range: 0.7 to 127.7 minutes) and 3.1 ±7.2 minutes in VPA (range: 0-38.3 minutes). Regression analysis revealed that VPA accounted for 4.1% of the variance in HDL-C (p=0.017), after controlling for age, gender, %BF and total PA. MPA did not significantly impact HDL-C, and neither MPA or VPA significantly contributed to TC, LDL-C, or TRIG after controlling for age, gender, %BF and total PA. CONCLUSION: Although these participants engaged in 30 minutes of moderate intensity activity, this amount of activity was not associated with higher HDL-C or lower TC, TRG or LDL-C. These data show that a higher quality of PA appeared to have a stronger impact on HDL-C levels. This work was partially supported by a Career Development Award from the National Institute on Aging (K01AG025962)