Background: During the last 25 years, the absolute number of cases of cardiovascular disease has increased in Europe. The goal in cardiac rehabilitation (CR) groups phase III is to motivate participants to demonstrate exercises independently of the group and self-reliant in long-term. In this context, it is of great importance to teach participants the appropriate training intensity. Adjusting the intensity of the training in CR groups is essential in order to avoid the dangers of overexertion and undertraining.
Aim: This study aimed to examine whether participants in CR groups could correctly assess their exertion and thus achieve their predefined training intensity.
Design: Observational study.
Setting: The setting of the study was an outpatient rehabilitation center.
Population: Forty-one people from CR groups phase III, with cardiovascular diseases, were included in the study.
Methods: The training focused on moderate-intensity activity. The Borg Scale was used to evaluate how participants rated their exertion. The heart rate was recorded with the Polar M600 during the entire training period to compare it with the estimated exertion.
Results: Sixty-five percent (65%) of the participants was trained within their prescribed training intensity. However, they rated the perceived exertion significantly higher than the measured HR (P<0.001). The difference between target training HR and measured HR was also significant (P=0.008). There were significant differences between the groups of moderate-intensity endurance training and moderate-intensity strength endurance training (P=0.002).
Conclusions: The participants in the CR groups could assess their own exertion moderately well. On the one hand, there were difficulties in accurately estimating the perceived exertion compared to the actual exertion. On the other hand, overloading and underloading were hardly detected.
Clinical rehabilitation impact: The perception of exertion must be improved by knowing one's own training heart rate and intensity. Therefore, wearables such as smartwatches could be useful monitoring aids for CR groups to check if the predefined training intensity will be reached.