The aim of this study was to investigate the effects of the difference in the ways to carry a baby using a baby carrier on the respiratory response during upslope walking. Fourteen healthy adults participated in this study. We set the individualized walking speed at 30% of the maximum oxygen uptake at 0% grade. The test began at 0% grade walking on the treadmill and increased by 2% every 5 min until 8%. The test was performed randomly in these two conditions: holding an infant model weighing approximately 15% of body weight in front of the subject with a baby carrier (F) and backpack with a baby carrier (B). Heart rate (HR), oxygen uptake (VO2), minute ventilation (VE), tidal volume (TV), respiratory exchange ratio (R), and respiratory rate (RR) were measured and the values from the last 1 min of each grade were averaged. HR, VO2, VE, TV, R, and RR significantly increased with increasing grade in each condition. There were no significant differences in interaction effects in HR, VO2, VE, TV, R, and RR. This study suggests that the difference in the ways to carry a baby using a baby carrier has no effects on the respiratory response during upslope walking at a speed corresponding to 30% of the maximum oxygen uptake at 0% grade until 8% grade.
