Table 1 Descriptive Statistics of UTIB, STIB, and RTIB (n = 341)

Age (years)

81 (6)

81 (4)

82 (6)

0.445

Women (%)

64

62

60

0.789

TIB (hr + min/night)

8 h 6 min (31 min)

8 h 32 min (1 h 19 min)

9 h 23 min (1 h 26 min)

<  0.001

Nap length (min/day)

43 (60)

36 (60)

41 (65)

0.835

SPPB total score

11 (3)

10 (3)

9 (4)

0.007

Accelerometer wear time (hr + min/day)

15 h 42 min (41 min)

15 h 23 min (1 h 6 min)

14 h 37 min (1 h 9 min)

<  0.001

Average CPM

2130 (768)

2102 (821)

1919 (824)

<  0.001

Highly Sedentary (%)

40

44

66

0.001

% of accelerometer wear time in SB (0–2302)

62 (14)

63 (14)

67 (15)

<  0.001

% of accelerometer wear time in intensity 2303–4999

23 (8)

23 (8)

21 (8)

0.026

% of accelerometer wear time in intensity ≥5000

14 (12)

14 (10)

11 (10)

0.006