Background : Active commuting is a practical way to increase Physical Activity (PA). E-cycling elicits Moderate-To-Vigorous Intensity PA (MVPA) with experimental health benefits. Less is known about real-life commuter e-cycling impact on changes in MVPA, total sedentary time (SED-time), fitness and perceived health.

Methods : 33 subjects (min-max: 27-70 years) imminently starting commuter e-cycling were monitored for 3 to 5 months. Declarative measurements in MVPA and SED-time were analyzed by multilevel modeling. Fitness (stress test and adiposity), SF12-v2 and EMAPS scores were pre-post compared.

Results : High and stable adherence to commuter e-cycling averaged 84% (95%CI, 75-91). Mean MVPA increased and plateaued after e-cycling onset, reaching 56.7 MET-h/week (95%CI 49.9-64.3) (+21 MET-h/week over baseline). Larger increases were associated with age and e-cycling volume. High SED-time persisted over time, averaging 8.6 hours/day (95%CI, 8.1-9.) though decreasing for older and initially most sedentary subjects. Cardiorespiratory fitness improved (+0.48 METs, p=0.001) as well as effort perception, heart-rate response, waist-to-height ratio and SF12-v2 Mental Score.

Conclusions : New commuter e-cyclists experience a major increase in MVPA and a persistent high sedentary behavior, associated with benefits in fitness, adiposity and perceived mental health. Results from this pilot study need to be confirmed in larger cohorts overtime.

Acutely, altitude may disrupt RPE association with sea level physiological responses, potentially altering workload selection during RPE production. To assess the impact of altitude on perceptually anchored intensity regulation. Males (n=6) and females (n=6) (VO₂ max = 50.1 + 7.8 ml?kg-1?min-1) completed counterbalanced production trials at sea level (SEA) and altitude (ALT, ~3400m) at RPE 4 and RPE 7, blinded to velocity (VEL) (1% grade). ANOVA’s (trial x RPE) showed no significant difference for VEL (m?min-1) within RPE 4 (SEA = 186 ± 23, ALT = 190 ± 29) or RPE 7 (SEA = 253 ± 31, ALT = 255 ± 40). However, PO₂ (%) was significantly lower for ALT within RPE 4 (96.4 ± 2.0 vs. 83.5 ± 5.4) and RPE 7 (97.2 ± 0.9 vs. 83.1 ± 3.4). HR (b?min-1) was significantly higher for ALT within RPE 4 (133 ± 19 vs. 153 ± 17), and RPE 7 (163 ± 18 vs. 175 ± 12). Session RPE was not significantly different between SEA and ALT within RPE 4 (ALT = 3.9 ± 0.8, SEA = 3.7 ± 0.7) or RPE 7 (ALT = 6.7 ± 0.5, SEA = 6.8 ± 0.8). Physiological variables (HR, PO₂) seem subsidiary to workload (VEL) in mediating the RPE production paradigm at altitude with those observations consistent for Session RPE. Correspondence between perceptual responses and other physiological factors, (lactate, VO₂, etc) at altitude warrants further consideration including responses across varying fitness levels, exercise modalities and following acclimatization periods.