Eccentric muscle work is when a muscle lengthens while applying force. Although eccentric muscle work is part of everyday life, e.g. whilst descending, it is not integrated in modern training protocols and its underlying physiological mechanisms are still incompletely understood. It was shown that muscles are able to perform four times as much power eccentrically compared to common concentric muscle work with a comparably very low oxygen demand and thus cardiovascular load. Thus, eccentric training may be of special interest for patients with cardiopulmonary diseases. Since much higher training intensities are achieved eccentrically, the training increase after a few weeks of eccentric training is huge compared to ordinary concentric training. In addition, it has been observed that these high intensities applied eccentrically lead also to a concentric gain in strength and are therefore transferable to everyday activities. Physical training has been shown to be beneficial in almost every cardiovascular disease, even in severely limited patients. However, training intensities may be very low in some patients with advanced cardiopulmonary disease, so some patients are physically almost unable to perform exercise on a beneficial level. Thus, for this collective, eccentric training may to be a very intriguing option. Patients with pulmonary vascular diseases such as pulmonary arterial and chronic thromboembolic pulmonary hypertension (PH) per definition reveal an elevated pulmonary artery pressure (PAP) along with an increased pulmonary vascular resistance (PVR). However, also other common diseases, such as left heart disease (LHD) or chronic obstructive pulmonary disease (COPD) are often associated with PH. The cardinal symptoms of PH is dyspnea on exertion leading to limited exercise performance, daily activity and quality of life. PH-patients also benefit from structured exercise training, but training intensities might be limited in patients with advanced disease. A few studies have investigated eccentric exercising in cardiopulmonary patients but none in PH. Most of these studies are in patients with coronary heart disease- (CHD) or COPD, including only few participants and often studies did not followed sound methodologies, such as randomized-controlled trial (RCT) protocols However, even in the hitherto limited patients´ investigated, eccentric training was assessed beneficial, feasible and safe.
The physiological cardiopulmonary response to eccentric exercising has not been investigated in patients with PH and the physiological basis to investigate such training opportunities is completely lacking.
The aim of this project is to investigate the cardiopulmonary effects of eccentric exercise in using solid randomized-controlled research protocols in cardiopulmonary diseases with focus on PH in order to provide a basis to the question of whether this promising training method could become established in cardiopulmonary rehabilitation, especially in patients with advanced disease and pulmonary hypertension.
