Muscle activation and energy expenditure of sedentary behavior alternatives in young and old adults

Abstract

The physiological mechanisms that underlie the metabolic benefits of breaking up sedentary behavior (SB) have yet to be determined. The purpose of this study is to compare energy expenditure (EE) and muscle activation (MA) responses to sitting and four SB alternatives in younger and older adults. Twenty-two adults, grouped by age (21-35 and 62-76 years), completed five randomly ordered 20 min tasks: (1) continuous sitting (Sit), (2) sitting on a stability ball (Ball), (3) continuous standing (Stand), (4) sitting interrupted by walking (S/W), and (5) sitting interrupted by standing (S/S). Muscle activation of two upper (trapezius and erector spinae) and two lower (rectus femoris and medial gastrocnemius) body muscles and total body EE were measured continuously. A linear mixed model using gender and age as a covariate with Bonferroni adjustment were used to determine significant differences between tasks. Collectively, S/W produced significantly higher MA and EE compared with Sit (p < 0.001). Stand and Ball provided significantly greater EE, but not MA, compared to Sit (p < 0.05), while S/S did not significantly change EE or MA compared to Sit. There were no net EE differences when comparing age groups across the tasks. Upper body MA was not consistent in both age groups across tasks. Specifically, during S/W the upper body MA of older adults (9.7 ± 1.5% MVC) was double that of young adults (4.8 ± 0.7% MVC, p = 0.006). Lower body MA responded similarly to all tasks in both age groups. Disrupting sitting with walking produced the largest increase in EE and MA compared to other SB alternatives in both age groups. These results are important considering the wide use of SB alternatives by researchers and public health practitioners.

Displacing Sedentary Behaviour with Light Intensity Physical Activity Spontaneously Alters Habitual Macronutrient Intake and Enhances Dietary Quality in Older Females

“…Given that both experimental groups similarly increased, this suggests that such an enhancement occurs irrespective of the pattern of prescribed LIPA. Together with the effect that LIPA has on stimulating skeletal muscle in older adults [ 73 ], secondary enhancements to dietary pro-anabolic potential may aid with perturbing the loss of skeletal muscle mass/function during aging (sarcopenia) [ 29 ].…”

Standing is not enough: A randomized crossover study on the acute cardiometabolic effects of variations in sitting in healthy young men

“…leg, thigh and back muscles; normalized against walking at 5 km/h on a treadmill) during 2 h of standing than during 2 sitting hours. In contrast, Lerma et al 13 found no significant differences in normalized upper (m. upper trapezius and m. erector spinae) and lower (m. medial gastrocnemius and m. rectus femoris) muscle activity between 20 min of standing and 20 min of sitting on a chair.…”

“…In line with this, we found no differences in activity of the rectus femoris, vastus lateralis and erector spinae muscles during active sitting compared to sitting on an office chair. Additionally, Lerma et al 13 found no differences in normalized (against maximal muscle contractions) upper (m. upper trapezius and m. erector spinae) and lower (m. medial gastrocnemius and m. rectus femoris) muscle activity during active sitting. Similarly, except for the left thoracic erector spinae, Gregory et al 27 found no significant differences in normalized (against maximal muscle contractions) muscle activity of the right thoracic erector spinae, left and right lumbar erector spinae, left and right rectus abdominis and left and right external oblique between sitting on a stability ball and sitting on an office chair in young adults (aged 25.4 ± 5.4 and 22.3 ± 1.0 years old men and women, respectively).…”

“…12 and 21-76-year-old adults 13 demonstrated significantly higher net energy expenditure (kcal/h, kcal/min) during respectively 15 and 23 min of sitting on a stability ball versus sitting on an office chair. When extrapolating their findings, Lerma et al 13 concluded that active sitting may result in an additional energy expenditure of 247 kcal/week versus sitting on an office chair. To date no previous studies have explored the acute cardiometabolic effects of prolonged sitting on a stability ball compared to sitting on an office chair.…”

Do Young People Ever Sit Still? Variations in Accelerometer Counts, Muscle Activity and Heart Rate across Various Sedentary Activities in Youth

“…Standing interruptions are increasingly used as a potential intervention to reduce prolonged sedentary behaviour in youth [ 7 ]. However, experimental studies in adults are inconclusive regarding whether muscle activity and body movement during standing are sufficient to counteract potential adverse cardiometabolic effects of prolonged sitting [ 8 , 9 ]. The extent to which body movement during standing is higher than during sedentary behaviour in young people is currently unknown.…”