Inactivity, exercise, and visceral fat. STRRIDE: a randomized, controlled study of exercise intensity and amount.
Despite the importance of randomized, dose-response studies for proper evaluation of effective clinical interventions, there have been no dose-response studies on the effects of exercise amount on abdominal obesity, a major risk factor for metabolic syndrome, diabetes, and cardiovascular disease. One hundred seventy-five sedentary, overweight men and women with mild to moderate dyslipidemia were randomly assigned to participate for 6 mo in a control group or for approximately 8 mo in one of three exercise groups: 1) low amount, moderate intensity, equivalent to walking 12 miles/wk (19.2 km) at 40-55% of peak oxygen consumption; 2) low amount, vigorous intensity, equivalent to jogging 12 miles/wk at 65-80% of peak oxygen consumption; or 3) high amount, vigorous intensity, equivalent to jogging 20 miles/wk (32.0 km). Computed tomography scans were analyzed for abdominal fat. Controls gained visceral fat (8.6 +/- 17.2%; P = 0.001). The equivalent of 11 miles of exercise per week, at either intensity, prevented significant accumulation of visceral fat. The highest amount of exercise resulted in decreased visceral (-6.9 +/- 20.8%; P = 0.038) and subcutaneous (-7.0 +/- 10.8%; P < 0.001) abdominal fat. Significant gains in visceral fat over only 6 mo emphasize the high cost of continued inactivity. A modest exercise program, consistent with recommendations from the Centers for Disease Control/American College of Sports Medicine (CDC/ACSM), prevented significant increases in visceral fat. Importantly, a modest increase over the CDC/ACSM exercise recommendations resulted in significant decreases in visceral, subcutaneous, and total abdominal fat without changes in caloric intake.
Division of Cardiology, Duke University Medical Center, Durham, NC 27710, USA.
Cris A
CA
Slentz
Lori B
LB
Aiken
Joseph A
JA
Houmard
Connie W
CW
Bales
Johanna L
JL
Johnson
Charles J
CJ
Tanner
Brian D
BD
Duscha
William E
WE
Kraus
D050153:Abdominal Fat / Q000000981:diagnostic imaging*; D000273:Adipose Tissue / Q000000981:diagnostic imaging*; D000328:Adult; D050171:Dyslipidemias / Q000000981:diagnostic imaging*; D002149:Energy Intake; D015444:Exercise; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010101:Oxygen Consumption; D012146:Rest; D040242:Risk Reduction Behavior; D012420:Running; D040521:Subcutaneous Tissue; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D014781:Viscera; D016138:Walking