The Seated Inactivity Trial (SIT): Physical Activity and Dietary Outcomes Associated With 8 Weeks of Imposed Sedentary Time

Abstract

Active adults did not alter physical activity or dietary behaviors during the imposed sedentary intervention. However, SIT reduced caloric intake from baseline to week 9, indicating a possible compensatory response to imposed sitting in active adults.

Exploring activity compensation amongst youth and adults: a systematic review

“…Studies were conducted in 10 different countries (see Table 1 ), with the majority occurring in the USA ( n = 13), the UK ( n = 13) and Australia ( n = 9). The age of participants ranged between 5 [ 72 ] to 63 [ 67 ] years, with 50% studies specifically focusing on children and/or adolescents ( n = 22; [ 20 , 21 , 33 , 36 , 39 , 41 – 44 , 47 – 52 , 55 , 58 , 63 – 65 , 71 , 72 ]) and 50% focusing on adults ( n = 22; [ 34 , 35 , 37 , 38 , 40 , 45 , 46 , 53 , 54 , 56 , 57 , 59 – 62 , 66 – 70 , 73 , 74 ]). Study sample sizes ranged from 16 participants [ 35 , 45 ] to 12,969 [ 69 ] participants.…”

“…The age of participants ranged between 5 [ 72 ] to 63 [ 67 ] years, with 50% studies specifically focusing on children and/or adolescents ( n = 22; [ 20 , 21 , 33 , 36 , 39 , 41 – 44 , 47 – 52 , 55 , 58 , 63 – 65 , 71 , 72 ]) and 50% focusing on adults ( n = 22; [ 34 , 35 , 37 , 38 , 40 , 45 , 46 , 53 , 54 , 56 , 57 , 59 – 62 , 66 – 70 , 73 , 74 ]). Study sample sizes ranged from 16 participants [ 35 , 45 ] to 12,969 [ 69 ] participants. Of the 44 studies included, the primary or secondary aim of 30 [ 20 , 21 , 33 , 35 – 39 , 41 – 44 , 48 , 50 – 56 , 59 , 64 , 66 , 68 – 74 ] and eight studies [ 34 , 38 , 40 , 47 , 57 , 58 , 62 , 63 ], respectively, was to examine activity compensation.…”

“…Few studies (26%) considered changes in activity across the whole activity spectrum [20,21,34,35,42,44,45,50,51,55,67], despite the co-dependency of activity intensities occurring within a finite period (e.g. 24 h) [77].…”

“…Two studies subjectively measured adults' physical activity using surveys [67,68]. Five studies (three in youth, two in adults) examined the whole activity spectrum [34,35,42,51,55]. One study, conducted with adolescents, examined the activity spectrum where LPA was classified as non-exercise activity thermogenesis (NEAT) [44].…”

“…timing of perturbation) [51]. Only 9 (20%) studies examined compensation across the activity spectrum [20,21,34,35,42,45,50,51,55].…”