Maximal instantaneous muscular power after prolonged bed rest in humans

Ferretti, G (author)

Minetti, AE (author)

Moia, C (author)

Rampichini, S (author)

Narici, MV (author)

(creator_code:org_t)

American Physiological Society, 2001
2001
English.
In: Journal of applied physiology (Bethesda, Md. : 1985). - : American Physiological Society. - 8750-7587 .- 1522-1601. ; 90:2, s. 431-435

Related links:: http://jap.physiolog...; show more...; http://kipublication...; https://doi.org/10.1...; show less...

Abstract Subject headings

A reduction in lower limb cross-sectional area (CSA) occurs after bed rest (BR). This should lead to an equivalent reduction in maximal instantaneous muscular power (W˙p) if the body segments' lengths remain unchanged. W˙p was determined during maximal jumps off both feet on a force platform before and on days 2, 6, 10, 32, and 48 after a 42-day duration BR. CSA of thigh muscles was measured by magnetic resonance imaging before and on day 5 after BR. Before BR, W˙p was 3.63 ± 0.43 kW or 48.6 ± 3.3 W/kg. On days 2 and 6 after BR, W˙p was reduced by 23.7 ± 6.9 and 22.7 ± 5.4% ( P < 0.01), respectively. Thigh extensors CSA (CSAext) was 16.7 ± 4.7% ( P < 0.01) lower than before. When normalized per CSAext, W˙p was reduced by only 4.8 ± 4.5% ( P < 0.05). By day 48 of recovery,W˙p had returned to baseline values. Therefore, ifW˙p is appropriately normalized for CSA of the extensor muscles, the reduction in CSAext explains most of the decrease in W˙p decrease after BR. Other factors such as a deficit in neural activation or a decrease in fiber-specific tension may account for only 5% of theW˙p loss after BR.

By the author/editor: Ferretti, G; Berg, HE; Minetti, AE; Moia, C; Rampichini, S; Narici, MV

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.