An interesting study suggests even short duration strength training delivers significant benefits.
(Lifting weights — how three seconds a day will make you stronger)
For their study, exercise scientists reporting in the Scandinavian Journal of Medicine & Science in Sports asked a small group (39) of healthy but sedentary men and women to perform the astonishingly brief arm-strengthening exercise with weights every day for a month.
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it was the eccentric lifters who made the biggest leap, ending the short trial with arm muscles 11.5 per cent stronger than when they started. “People think you have to spend vast amounts of time exercising to improve their muscle strength, but that’s not the case,” Nosaka says. “Our study results suggest that a very small amount of exercise stimulus — even 60 seconds in four weeks — can increase muscle strength and that every muscle contraction counts.”