Table 1.

Baseline characteristics according to thirds of muscular strength, Aerobics Center Longitudinal Study, 1980 to 2003

CharacteristicAll (n = 8,677)Muscular strength thirds
Lowest (n = 2,892)Middle (n = 2,894)Upper (n = 2,891)P for linear trend
Age, mean (SD), y42.7 (9.5)43.3 (9.5)42.7 (9.4)42.2 (9.7)<0.0001
BMI, mean (SD), kg/m225.8 (3.5)26.9 (4.2)25.5 (3.0)25.1 (2.7)<0.0001
Waist circumference, mean (SD), cm92.7 (10.1)97.5 (10.9)92.0 (8.8)88.6 (8.3)<0.0001
Percent body fat, mean (SD)20.3 (6.2)23.6 (5.9)20.1 (5.3)17.1 (5.5)<0.0001
Maximal METs, mean (SD)12.5 (2.5)11.5 (2.3)12.5 (2.3)13.4 (2.4)<0.0001
Treadmill time, mean (SD), min19.7 (4.9)17.7 (4.8)19.7 (4.6)21.6 (4.5)<0.0001
Bench press, mean (SD)
    kg71.5 (17.4)61.6 (12.1)69.6 (12.6)83.3 (19.0)<0.0001
    kg/kg of body weight0.9 (0.2)0.7 (0.1)0.9 (0.1)1.1 (0.2)<0.0001
Leg press, mean (SD)
    kg136.7 (27.0)124.8 (24.7)135.5 (23.4)149.9 (26.5)<0.0001
    kg/kg of body weight1.7 (0.3)1.4 (0.2)1.7 (0.2)1.9 (0.3)<0.0001
Lipids, mean (SD), mg/dL
    Total cholesterol211 (44)214 (41)212 (51)207 (40)<0.0001
    High-density lipoprotein cholesterol46 (12)45 (12)46 (12)47 (12)<0.0001
    Triglycerides130 (106)142 (105)131 (123)117 (85)<0.0001
Fasting blood glucose, mean (SD), mg/dL100 (14)101 (17)99 (13)98 (11)<0.0001
Blood pressure, mean (SD), mm Hg
    Systolic119 (13)120 (13)118 (12)119 (13)<0.0001
    Diastolic79 (9)80 (9)79 (9)79 (9)<0.0001
Current smoker, n (%)1,313 (15.1)492 (17.0)455 (15.7)366 (12.7)<0.0001
Alcohol intake (≥5 drinks/wk), n (%)4,300 (49.6)1,431 (49.5)1,446 (50.0)1,423 (49.2)0.84
Sedentary*, n (%)1,725 (19.9)746 (25.8)574 (19.8)405 (14.0)<0.0001
Baseline medical conditions, n (%)
    Hypercholesterolemia1,875 (21.6)687 (23.8)632 (21.8)556 (19.2)<0.0001
    Diabetes mellitus208 (2.4)100 (3.5)49 (1.7)59 (2.0)0.0005
    Hypertension2,166 (25.0)848 (29.3)688 (23.8)630 (21.8)<0.0001
    Cardiovascular disease111 (1.3)49 (1.7)33 (1.1)29 (1.0)0.02
  • Abbreviations: MET, maximal metabolic equivalents achieved during the treadmill test; kg, kilograms.

  • * Participants were defined as sedentary if they reported no leisure-time physical activity in the 3 mo before baseline examination.

  • Defined as the presence of hypercholesterolemia [history of physician-diagnosed high cholesterol level or measured fasting total cholesterol level ≥240 mg/dL (6.20 mmol/L)] or diabetes [history of physician diagnosis, use of insulin, or measured fasting glucose level ≥126 mg/dL (7.0 mmol/L), or self-reported diabetes]; or hypertension (history of physician diagnosis or resting systolic blood pressure ≥140 mm Hg or diastolic blood pressure ≥90 mm Hg).