Table 2.

Estimated Values for , Knee Extensor and Flexor Strength, and Daily Physical Activity and Sedentary Behavior and Significance Level of Change Over Time^a

Physical Fitness	Mean (SE) at:		Change From t1 to t2b	95% CI for Change	Cohen dc	P
	6 mo (t1)	12 mo (t2)
Cardiorespiratory fitness
, mL/kg/min	22.79 (0.94)	24.20 (0.91)	+1.417	0.170 to 2.664	0.257	.027d
HRpeak, % of predicted HRmax	88.59 (2.37)	90.42 (2.32)	+1.824	−1.398 to 5.054	0.132	.255
RERpeak,	1.13 (0.01)	1.19 (0.02)	+0.058	0.034 to 0.081	0.653	<.001d
Knee muscle strength
PText, N·m/kg	1.38 (0.06)	1.45 (0.06)	+0.071	−0.004 to 0.146	0.185	.061e
PTflex, N·m/kg	0.61 (0.04)	0.64 (0.04)	+0.026	−0.022 to 0.073	0.119	.281

^aAll determinants were entered separately with adjustment for sex and age. CI = confidence interval; HR_max = maximum predicted heart rate; HR_peak = peak heart rate; PT_ext = peak torque of the knee extensors; PT_flex = peak torque of the knee flexors; RER_peak = peak respiratory exchange ratio;  = peak carbon dioxide uptake;  = peak oxygen uptake.

^bEstimated mean change over follow-up time.

^cCohen d = . μ2 = standardized mean t2; μ1 = standardized mean t1; Σσ = pooled standardized standard deviation.

^dSignificant difference (P < .05).

^eNonsignificant trend for a difference (P  < .10).