Introduction: Nordic pole walking (NW) has gained significant attention to increase caloric expenditure vs. conventional walking without poles. However data are pending regarding the hemodynamic response of Nordic pole walking vs. walking. We hypothesized that NW increases cardiac output stronger than conventional walking at a given perceived level of physical exertion in a field test.
Methods: 48 participants (51+/-11 years, BMI 25+/-3) were included and randomised for either Nordic pole or conventional 30 min of outdoor walking. Heart rate (HR), stroke volume (SV), and cardiac output (CO) were determined non-invasively using continuous CW-Doppler ultrasound (USCOM) for four times (before, immediately after physical exercise and after the first and third minute during recovery). Perceived level of exertion was 13+/-1 (NW) and 13+/-2 (walking, n.s.).
Results: Immediately after peak exercise, heart rate increased significantly from 74+/-9 bpm to 123+/-20 bpm (66+/-4%, NW, p<0.05) and from 73+/-7 bpm to 137+/-30 bpm (73+/-7%, walking, p<0.05). CW-Doppler determined stroke volume increased from 48+/-10 ml to 59+/-24 ml (23+/-4%, p<0.05) and 45+/-20 ml to 50+/-13 ml (11+/-3%, p<0.05) immediately after peak exercise. Consecutive cardiac output increased from baseline 3.5+/-0.9 l/min to 7.3+/-3 l/min (NW) and from 3.4+/-1.2 l/min to 6.8+/-2.2 l/min (walking), respectively (both p<0.05). During recovery stroke volume significantly faster diminished within the first minute of recovery vs. heart rate and cardiac output in both groups. No changes between NW and walking were evident in hemodynamic parameters.
Conclusion: No significant difference in the extent of cardiac output up-regulation between Nordic pole walking and walking at a given level of physical exertion was found. Hemodynamic field testing is feasible using the portable CW-Doppler ultrasound USCOM.