Gymnastik- och idrottshögskolan, GIH

Debattartikeln tar upp Naturvårdsverkets förhållningssätt till att klassa elcykeln och att nyttja den för att besöka naturområden.

Purpose: Studies indicate that the rated perceived exertion (RPE) during physical exercise can be lower in field environments than indoors. The environmental conditions of those studies are explored. Furthermore, we study if the same phenomenon is valid when cycling indoors versus in cycle commuting environments with high levels of stimuli from both traffic and suburban-urban elements. 

Methods: Twenty commuter cyclists underwent measurements of heart rate (HR) and oxygen uptake (V̇O2) and RPE assessments for breathing and legs, respectively, while cycling in both laboratory and field conditions. A validated mobile metabolic system was used in the field to measure V̇O2. Three submaximal cycle ergometer workloads in the laboratory were used to establish linear regression equations between RPE and % of HR reserve (%HRR) and %V̇O2max, separately. Based on these equations, RPE from the laboratory was predicted and compared with RPE levels at the participants’ individual cycle commutes at equal intensities. The same approach was used to predict field intensities and for comparisons with corresponding measured intensities at equal RPE levels.    

Results: The predicted RPE levels based on the laboratory cycling were significantly higher than the RPE levels in cycle commuting at equal intensities (67% of HRR; 65% of V̇O2max). For breathing, the mean RPE levels were; 14.0-14.2 in the laboratory and 12.6 in the field. The corresponding levels for legs were; 14.0-14.2 and 11.5. The range of predicted field intensities in terms of %HRR and %V̇O2max was 46-56%, which corresponded to median differences of 19-30% compared to the measured intensities in field at equal RPE.  

Conclusion: The cycle commuters perceived a lower exertion during their cycle commutes compared to ergometer cycling in a laboratory at equal exercise intensities. This may be due to a higher degree of external stimuli in field, although influences from other possible causes cannot be ruled out.

Background 

It is important to examine how motorized traffic variables affect pedestrians along a gradient from rural to inner urban settings.

Methods

Relations between pedestrians´ perceptions of four traffic variables and appraisals of route environments as hindering – stimulating for walking as well as unsafe – safe for reasons of traffic, were therefore studied in the inner urban area of Stockholm, Sweden (n = 294). The pedestrians rated their perceptions and appraisals with the Active Commuting Route Environment Scale (ACRES). Correlation, multiple regression, and mediation analyses were used to study the relationships between the traffic variables and the outcome variables. 

Results 

Noise related negatively to both hindering – stimulating for walking, and to unsafety – safety for traffic reasons. Vehicle speed related negatively to unsafety – safety for traffic reasons. Furthermore, vehicle speed protruded as an important origin of the deterring effects of traffic among those who commute by foot. 

Conclusion

The study shows the value of both partial and simultaneous analyses of the effect of all four traffic variables in relation to outcome variables relevant for walking. 

Background

Every walk takes place in a route environment, and it can play an important role in deterring or facilitating walking, and will always affect the environmental unwell – wellbeing of pedestrians. The aim of this study is to illuminate which the important route environmental variables are in this respect. The focus is therefore on pedestrians´ perceptions of route environmental variables and how they relate to overall appraisals of route environments as hindering – stimulating for walking and unsafe – safe for reasons of traffic. 

Methods

Commuting pedestrians in the inner urban area of Stockholm, Sweden (n = 294, 49.5 ± 10.4 years, 77% women), were recruited via advertisements. They evaluated their own commuting route environments using a self-report tool, the Active Commuting Route Environment Scale (ACRES). Correlation, multiple regression, and mediation analyses were used to study the relationships between the variables and the outcome variables.

Results

Aesthetics and greenery appear to strongly stimulate walking, whereas noise, a proxy for motorized traffic, hinders it. Furthermore, aesthetics is positively related to traffic safety, whereas conflicts have the opposite role. Conflicts is an intermediate outcome, representing several basic environmental variables, whereof some were directly and negatively related to unsafe – safe traffic.

Conclusion 

Route environmental variables appear to be potent factors in deterring or facilitating walking. This knowledge is of importance for policymakers and urban planners when designing route environments with the aim of attracting new pedestrians, and simultaneously stimulating those who already walk to keep on.

Det kan inte vara acceptabelt att tusentals svenskar ska bli sjuka varje år på grund av luften de andas. Nu finns ett guldläge för regeringen att agera, skriver en bred koalition av folkhälsoaktörer.

BACKGROUND: The heart rate (HR) method enables estimating oxygen uptake (V̇O₂) in physical activities. However, there is a paucity in knowledge about the interchangeability of this method when applied to cycling, walking and running. Furthermore, with the aim of optimization, there is a need to compare different models for establishing HR-V̇O₂ relationships.

METHODS: Twenty-four physically active individuals (12 males and 12 females) participated. For each participant, two models of HR-V̇O₂ relationships were individually established in ergometer cycling, level treadmill walking and running. Model 1 consisted of five submaximal workloads, whereas model 2 included also a maximal workload. Linear regression equations were used to estimate V̇O₂ at seven intensity levels ranging between 25 and 85% of heart rate reserve (HRR). The estimated V̇O₂ levels were compared between the exercise modalities and models, as well as with data from a previous study.

RESULTS: A high level of resemblance in estimated V̇O₂ was noted between running and cycling as well as between running and walking, with both model 1 and model 2. When comparing walking and cycling, the V̇O₂ levels for given intensities of %HRR were frequently slightly higher in walking with both models (range of significant differences: 5-12%). The variations of the estimated individual V̇O₂ values were reduced when using model 2 compared to model 1, both between and within the exercise modalities.

CONCLUSION: The HR method is optimized by more workloads and wider ranges. This leads to overall high levels of interchangeability when HR methods are applied in ergometer cycling, level treadmill walking and running.