Field evaluation of energy expenditure from continuous and intermittent walking in women.
BACKGROUND
Recent physical activity recommendations suggest that comparable amounts of prescribed physical activity, done as a single continuous bout or as a set of intermittent bouts, will produce equal amounts of energy expenditure (EE) during the prescribed activity as well as throughout the day.


OBJECTIVE
In a field setting, we tested two hypotheses: (1) continuous and intermittent walking conditions will result in significantly greater total daily EE than a control condition, and (2) continuous and intermittent walking conditions will result in similar total daily


METHODS
Thirty women (mean age [yr] = 43.7+/-5.8; mean body mass index [kg x m(-2)]= 24.7+/-4.0) participated in a repeated-measures design so that each woman participated in three walking conditions on successive days of the week: a single 30-min brisk walk (continuous): three 10-min brisk walks (intermittent); and no activity (control). Throughout the study protocol, women wore a TRITRAC-R3D accelerometer programmed to estimate EE in 2-min intervals.


RESULTS
Mean total EE estimates (kcal) for the three walking conditions were as follows: continuous: 2181+/-308; intermittent: 2121+/-305; and control: 1948+/-270. A repeated-measures analysis of variance omnibus test indicated that EE differed significantly by experimental condition [F(2,58) = 40.2, P < 0.001). To test the first hypothesis, contrasts were examined revealing that EE in the continuous and intermittent conditions was significantly greater than EE in the control condition [F(1,29) = 58.2, P < 0.001]. To test the second hypothesis, contrasts revealed that EE in the continuous condition was significantly greater than EE in the intermittent condition [F(1,29) = 7.0, P = 0.013].


CONCLUSIONS
For the purposes of total EE, selecting a continuous mode of walking may offer additional benefit over an intermittent mode, given the same total prescribed duration.
Fulton
J E
JE
Division of Nutrition and Physical Activity, Centers for Disease Control and Prevention, Atlanta, GA 30341-3724, USA. jkf2@cdc.gov
Mâsse
L C
LC
Tortolero
S R
SR
Watson
K B
KB
Heesch
K C
KC
Kohl
H W
HW
Blair
S N
SN
Caspersen
C J
CJ
D000328:Adult; D004734:Energy Metabolism / Q000502:physiology*; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D008875:Middle Aged; D016138:Walking / Q000502:physiology*