Effect of short moderate intensity exercise bouts on cardiovascular function and maximal oxygen consumption in sedentary older adults

Aim To investigate effect of <10 min moderate intensity exercise on cardiovascular function and maximal oxygen consumption ( <m:math xmlns:m="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <m:mstyle displaystyle="true" scriptlevel="0"> <m:mrow> <m:mover> <m:mi>V</m:mi> <m:mrow> <m:mo>˙</m:mo> </m:mrow> </m:mover> </m:mrow> </m:mstyle> </m:math> O 2 max) among sedentary adults. Methods We studied 53 sedentary urbanites aged ≥50 years, randomised into: (1) male (M S ) and (2) female (F S ) undertaking three short-duration exercise (5–10 min) daily, and (3) male (M L ) and (4) female (F L ) exercising 30–60 min 3–5 days weekly. Resting systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate and <m:math xmlns:m="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <m:mover accent="true"> <m:mrow> <m:mi>V</m:mi> </m:mrow> <m:mo>˙</m:mo> </m:mover> </m:math> O 2 max were measured at baseline and 8 weekly for 24 weeks. Results At baseline, 50% M S , 61.5% M L , 53.8% F S and 53.8% F L had SBP ≥120 mm Hg, and 14.3% M S , 53.8% M L , 23.1% F S and 38.5% F L had DBP ≥80 mm Hg. At 24 weeks, where SBP remained ≥120 mm Hg, values decreased from 147±19.2 to 132.3±9.6 mm Hg (50% of M S ), from 144±12.3 to 128±7.0 mm Hg (23.1% of M L ), from 143.1±9.6 to 128.0±7.0 mm Hg (53.8% of F S ) and from 152.3±23.7 to 129±3.7 mm Hg (30.8% of F L ). For DBP ≥80 mm Hg, M S and F S percentages maintained, but values decreased from 101±15.6 to 84.5±0.7 mm Hg (M S ) and 99.0±3.6 to 87.7±4.9 mm Hg (F S ). In M L and F L , percentage with DBP ≥80 mm Hg dropped to 15.4% (86.1±6.5 to 82.5±3.5 mm Hg) and (91.4±5.3 to 83.5±0.71 mm Hg). <m:math xmlns:m="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <m:mover accent="true"> <m:mrow> <m:mi>V</m:mi> </m:mrow> <m:mo>˙</m:mo> </m:mover> </m:math> O 2 max increased from 26.1±4.4 to 32.0±6.2 for M S , from 25.8±5.1 to 28.8±5.4 for M L (group differences p=0.02), from 20.2±1.8 to 22.7±2.0 for F S and from 21.2±1.9 to 24.2±2.7 for F L (groups differences p=0.38). Conclusion Accumulated moderate intensity exercise bouts of <10 min confer similar-to-better cardiovascular and <m:math xmlns:m="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <m:mover accent="true"> <m:mrow> <m:mi>V</m:mi> </m:mrow> <m:mo>˙</m:mo> </m:mover> </m:math> O 2 max improvements compared with current recommendations among sedentary adults.