Table 1.
Baseline characteristics among 2,261 male participants according to weekly level of exercise (IVF Study, 1993–2003)
|
Characteristica |
Regular exercise | |||||
|---|---|---|---|---|---|---|
| No exercise (N=975) |
All categories (N=1,286) |
<20 MET- hrs/wk (N=503) |
20–39 MET- hrs/wk (N=489) |
≥40 MET- hrs/wk (N=294) |
P-trendb | |
| Age, years (mean) | 36.8 | 37.1 | 37.3 | 36.9 | 37.2 | 0.84 |
| White (%) | 90.3 | 92.2 | 89.4 | 95.1 | 92.6 | 0.01 |
| Body mass index, kg/m2 (mean) | 25.0 | 23.2 | 23.4 | 22.9 | 23.1 | <0.001 |
| Education (%) | ||||||
| Less than College | 36.5 | 19.5 | 18.5 | 18.5 | 22.6 | <0.001 |
| College | 36.1 | 35.6 | 34.8 | 35.7 | 36.2 | 0.97 |
| Graduate school | 27.4 | 44.9 | 46.6 | 45.8 | 41.2 | <0.001 |
| Multivitamin use (%) | 39.1 | 50.7 | 50.0 | 48.8 | 54.0 | <0.001 |
| Current smoker (%) | 16.4 | 5.2 | 5.2 | 4.4 | 6.5 | <0.001 |
| Pack-years of smoking (mean) | 5.0 | 2.2 | 2.6 | 1.9 | 1.9 | <0.001 |
| Alcohol, g/wk (mean) | 66.0 | 66.7 | 60.9 | 70.7 | 69.2 | 0.30 |
| Caffeine, mg/wk (mean) | 1,970 | 1,702 | 1,694 | 1,674 | 1,771 | 0.003 |
| Diabetes treated with medication (%) | 1.0 | 0.9 | 0.5 | 0.6 | 1.6 | <0.001 |
| Hypertension (%) | 10.5 | 5.6 | 5.2 | 7.0 | 2.9 | <0.001 |
| History of urogenital anomaly (%) | 9.6 | 11.6 | 13.5 | 12.8 | 7.3 | 0.96 |
| History of STD/prostate infection (%) | 13.7 | 13.3 | 12.8 | 14.9 | 11.0 | 0.62 |
| History of male factor infertility (%) | 27.0 | 25.8 | 26.5 | 27.3 | 22.6 | 0.24 |
| IVF or GIFT before entering study (%) | 14.3 | 12.5 | 14.1 | 12.0 | 11.1 | 0.08 |
| Wear briefs only (%) | 56.5 | 49.6 | 52.1 | 50.6 | 43.3 | <0.001 |
| Baths preferred to showers (%) | 3.3 | 2.0 | 1.8 | 1.2 | 4.2 | 0.41 |
N = number of male participants.
a
Characteristics are presented as means or percents within exercise categories and are standardized to age distribution of sample.
b
Test of difference in baseline characteristic across physical activity categories (none, <20, 20–39, ≥40 MET-hrs/wk).