Abstract
Background: Nordic walking (NW) requires more energy compared with conventional walking (W). However, the metabolic equation for NW has not been reported. Therefore, this study aimed to characterize responses in oxygen uptake (V̇O2), minute ventilation (V̇E), heart rate (HR), systolic blood pressure (SBP), and surface electromyography (sEMG) of the upper and lower limb muscles during NW and W and to develop a metabolic equation for energy expenditure (E) of NW.Methods: Fifty healthy young men constituted our sample (aged 23.7 ± 3.0 years). Two randomly assigned walking tests (NW and W) on a treadmill at a predetermined stepwise incremental walking speed (3–5 km·h-1) and grade (0%–7%). The V̇O2, V̇E, HR, and SBP were measured. The sEMG signals of the three upper limb muscles and three lower limb muscles in their right body were recorded. Linear regression analysis was used to draw estimation of EE during W and NW.Results: V̇O2 (+15.8%), V̇E (+17.0%), RR (+18.2%), HR (+8.4%), and SBP (+7.7%) were higher in NW than in W. NW resulted in increased muscle activity in all of the upper limb muscles (P<.05). In the lower limb, sEMG activities in two of the three lower limb muscles were increased in NW than in W only during level walking (P<.05). EE during W and NW was estimated as follows: EW = 4.4 + 0.09 × speed + 1.20 × speed × grade; ENW = 6.1 + 0.09 × speed + 1.19 × speed × grade.Conclusion: NW showed higher work intensity than W, with an oxygen consumption difference of 1.7 mL·kg-1·min-1. The coefficients were not different between the two walking methods. NW involved more muscles of the upper body than W.
The Comparative Analysis of EMG Activities on The Upper and Lower Limb Muscles during Nordic Walking
