Table 3 Physical activity and physical performance by gender group
MHD patients N = 72 MHD:male vs. female Normal controls N = 39 Normals: male vs. female Males: MHD vs. normals Females: MHD vs. normals
Males N = 49 Females N = 23  p Males N = 23 Females N = 16  p  p  p
Age (years) 51.8 ± 13.0 53.8 ± 13.0 0.545 51.3 ± 14.7 50.6 ± 9.5 0.868 0.884 0.407
Vintage (months) 46.9 (46.7) 51.4 (72.4) 0.018 – – – – –
Physical activity
 Human activity profile
  Maximum activity score 84 (10) 82 (18) 0.155 92 (5) 89.5 (4) 0.472 <0.0001 <0.0001
  Adjusted activity score 76 (21) 69 (26) 0.319 91 (4) 88 (4) 0.285 <0.0001 <0.0001
 Time spent by monitor (%)
  Sleep or inactive 82.0 ± 5.8 81.7 ± 6.0 0.840 72.9 ± 6.1 72.7 ± 6.0 0.920 <0.0001 <0.0001
  Light activity 14.2 ± 4.4 14.9 ± 4.5 0.534 19.3 ± 4.3 21.0 ±4.6 0.245 <0.0001 0.0002
  ≥ Moderate activity 3.8 ± 2.0 3.3 ± 2.2 0.341 7.8 ± 3.3 6.4 ± 2.3 0.151 <0.0001 <0.0001
Average daily physical activity (vector magnitude)
  Daily physical activity (mean of 7 days) 421,539 (260,044) 365,050 (184,522) 0.398 644,556 (305,427) 596,642 (244,376) 0.435 <0.0001 <0.0001
  Day of HD 324,559 (203,547) 329,942 (135,789) 0.315 – – – – –
  1-day-post-HD 443,085 (261,536) 442,355 (211,902) 0.438 – – – – –
  2-days-post HD 398,185 (268,775) 360,273 (273,908) 0.887 – – – – –
Physical performance
 6-min walk distance (meters) 467.6 ± 98.9 385.3 ± 147.6 0.007 632.9 ± 60.7 595.5 ± 61.9 0.068 <0.0001 <0.0001
 Sit-to-stand test (cycles per 30 s) 16.5 ± 5.6 14.7 ± 4.2 0.175 28.1 ± 3.9 23.6 ± 6.3 0.009 <0.0001 <0.0001
 Stair-climbing test (seconds per 22 stairs) 13.5 ± 5.0 20.8 ± 17.2 0.008 9.6 ± 1.2 10.2 ± 1.0 0.109 <0.0001 0.008
Data expressed as mean ± standard deviation. Non-normally distributed data are expressed as median values with the interquartile range (IQR. i.e., the arithmetic difference between the 25th percentile value and the 75th percentile value) shown in parentheses