Table 2.

Mean (±SD) muscle strength and endurance before (Pre) and after bed rest (Post), the mean percent change (Δ) from pre‐ to post‐bed rest, and the effect of bed rest on each variable within groups

	Measure	Units	Men				Women
			Pre	Post	Δ	P	Pre	Post	Δ	P
Control
Concentric knee extensiona	Peak Torque	N‐m	189 ± 44	151 ± 37	−20%	0.0004	113 ± 31	102 ± 31	−10%	0.22
Concentric knee flexor	Peak Torque	N‐m	88 ± 15	77 ± 13	−13%	0.0009	52 ± 12	48 ± 11	−8%	0.11
Isometric knee extensiona	Peak Torque	N‐m	221 ± 59	198 ± 63	−10%	0.02	147 ± 41	124 ± 34	−16%	0.02
Isometric knee flexion	Peak Torque	N‐m	82 ± 15	76 ± 20	−7%	0.11	49 ± 10	46 ± 10	−6%	0.37
Concentric knee extensiona	Total Work	N‐m	2458 ± 743	2112 ± 531	−14%	0.0000	1442 ± 353	1400 ± 379	−3%	0.36
Concentric knee flexion	Total Work	N‐m	1322 ± 272	1120 ± 198	−15%	0.0002	801 ± 179	702 ± 204	−12%	0.03
Concentric ankle extension	Peak Torque	N‐m	94 ± 18	81 ± 26	−14%	0.0005	54 ± 14	49 ± 12	−9%	0.09
Concentric ankle flexion	Peak Torque	N‐m	32 ± 7	29 ± 7	−9%	0.004	22 ± 4	21 ± 6	−5%	0.10
Leg lean tissue mass	Lean mass	kg	18.5 ± 4.2	17.2 ± 3.2	−7%	0.0002	12.4 ± 1.4	12.3 ± 1.3	−1%	0.78
Exercise
Concentric knee extensiona	Peak Torque	N‐m	183 ± 48	173 ± 57	−5%	0.21	112 ± 24	104 ± 28	−7%	0.35
Concentric knee flexor	Peak Torque	N‐m	86 ± 24	77 ± 26	−10%	0.003	50 ± 11	50 ± 13	0%	0.86
Isometric knee extensiona	Peak Torque	N‐m	206 ± 55	197 ± 61	−4%	0.28	136 ± 32	121 ± 31	−11%	0.10
Isometric knee flexion	Peak Torque	N‐m	84 ± 25	74 ± 21	−12%	0.01	50 ± 11	45 ± 9	−10%	0.18
Concentric knee extensiona	Total Work	N‐m	2272 ± 911	2209 ± 978	−3%	0.16	1403 ± 360	1440 ± 398	+3%	0.42
Concentric knee flexion	Total Work	N‐m	1283 ± 488	1123 ± 360	−12%	0.001	765 ± 146	705 ± 153	−8%	0.16
Concentric ankle extension	Peak Torque	N‐m	87 ± 23	83 ± 21	−5%	0.27	52 ± 12	55 ± 11	+6%	0.42
Concentric ankle flexion	Peak Torque	N‐m	30 ± 7	28 ± 8	−7%	0.002	21 ± 3	20 ± 4	−5%	0.03
Leg lean tissue mass	Lean mass	kg	17.0 ± 3.9	16.5 ± 3.2	−3%	0.10	12.3 ± 1.3	12.5 ± 1.4	+2%	0.42

^aAnalysis performed with the pre‐bed rest score as a covariate. With Bonferroni adjustment for multiple sampling, a conservative interpretation is that a P value of <0.0125 is significant.