Background: Walking for health and fitness is one of the most popular forms of physical activity. The purpose of this investigation was to evaluate the physiological differences in
walking at self-selected paces for three 10 minute bouts (3-10) compared to one 30 (1-30) minute bout.
Methods: Participants were 19 females aged 35.6 ± 14.2 yrs (Mean ± SD). The subjects were recruited from local health clubs, churches and university classes. Participants reported to
the Human Performance Lab for initial evaluations including health history, weight (kg), height (m), and body composition (bioelectrical impedance). Caloric expenditure, HR, and VO2 were evaluated
during a maximal treadmill exercise test (modified Bruce protocol). Expired gas fractions were evaluated with a metabolic cart (ParvoMedicsTrueOne® 2400 Sandy, UT). The test was terminated when the
participants reached at least two of the criteria for maximal oxygen consumption (VO2max) as follows: a plateau in VO2 (± 2 ml.kg-1.min-1) with increasing work rate; respiratory exchange ratio > 1.10;
Ratings of Perceived Exertion of at least an 8 out of 10; or volitional fatigue. On separate occasions subjects walked on an indoor track at self-selected paces for 1-30 min continuous bout, and on
another day 3-10 min bouts spread out over the day. The indoor track was calibrated with a distance wheel and the environmental conditions were not different. Total distance walked (TD) was measured
and HR was continuously monitored with a Garmin HR monitor. Paired T-tests were used to compare distance, time, HR, and Kcals for the two walking conditions (P<0.05). Kcals were determined based on
the relationship between TM HR and VO2.
Results: The distance walked in the three 3-10 minute bouts was 2996.76 ± 323.46 meters, as compared to 2832.44 ± 273.56 meters for the 1-30 minute bout (P < 0.000). Walking speed for
the 3-10 minute bouts was 99.77 ± 10.78 m/min as compared to 94.41 ± 9.25 m/min for the 1-30 minute bout (P = 0.19). HR values were 123 ± 15 for 1-30 and 126 ± 17 for the 3-10 min bouts (P = 0.09).
The mean Kcals expended for the 3-10 minute bouts was 153.05 Kcals as compared to 142.02 Kcals for 1-30 min condition.
Conclusions: There were significantly higher values in total walking distance, speed, and Kcals in the 3-10 min bouts as compared to 1-30 min bout. Mean HR values for the two
conditions were similar. This investigation found that when walking for equal time periods, shorter walking bouts multiple times per day can be as effective as, or even more intense, than walking for
30 continuous min.