The investigators will investigate the response of an individualized exercise training program on quality of life, cardiorespiratory fitness and disease-specific markers in patients with myeloproliferative neoplasms (MPN). To this end, the investigators will randomly assign patients with MPN to a training group and a waiting control group.

The training group will undergo an individually tailored exercise training program for three months, while the control group will maintain their usual lifestyle for three months and then has the opportunity to undergo the three-month intervention program. At the beginning and at the end of the three-month intervention phase, the investigators will evaluate physical performance, daily physical activity, muscular strength, and self-reported outcomes and compare them between the training and the control group, in order to assess potential benefits of the exercise training program.

To date, there have been no randomized intervention studies on the effects of physical training in patients with myeloproliferative neoplasms (MPN). Current leukemia and hematology society recommendations and guidelines support the engagement in regular physical activity to improve cardiovascular health, reduce fatigue, and enhance quality of life. However, no disease-specific exercise guidelines for patients with MPNs exist due to the lack of appropriate clinical trials adressing this issue. The aim of the planned study is to investigate an individually tailored physical exercise program with online monitoring for patients with MPN and to measure its effects on quality of life and physical fitness. The primary endpoint is performance (watts) at the respiratory compensation point (RCP), an established marker of submaximal physical performance.

This is a monocentric, prospective, randomized intervention study with a waiting control group. Randomization is performed in a 1:1 ratio to the study groups and is stratified for gender (male/female). The persons conducting the exercise tests (but not the trainers guiding the training program) are blinded so that there is no targeted motivation during the performance test of the intervention group.

Description of the study procedure: The intervention lasts 3 months. The waiting-control group receives the intervention after the 3-month control phase. Participants receive feedback every second week during intervention via telemonitoring or in person, depending on their distance from the study center.

The intervention includes structured, individually tailored physical training with feedback and adjustments to physical activity intensity and content. Daily activity is monitored using a wearable activity device (Garmin smartwatch). An individual training plan includes moderate endurance and strength exercises 3 times a week, with the goal of being physically active for 150 minutes per week. To avoid overexertion, training is monitored by measuring heart rate and providing individual feedback to patients.

The primary evaluation follows the intention-to-treat (ITT) principle, with missing values at the final examination replaced by the corresponding baseline values. An analysis of covariance (ANCOVA) model is used for performance at the RCP, with the mean after-before difference as the primary target variable. Covariates included in the model are the therapy group (intervention and waiting list control), the baseline values of the performance parameter, and gender (female/male). The intervention is considered successful if the lower limit of the two-sided 95% confidence interval is greater than 0.

Inclusion Criteria:

• age ≥ 18 years
• diagnosis of myeloproliferative neoplasia according to WHO/ICC 2022.

Exclusion Criteria:

• current participation in another intervention study
• the presence of any diseases or functional impairments that, in the opinion of the examining physician, exclude participation in a physical training intervention.

De-identified individual participant data that underlie the results of the publication will be available upon reasonable request.

beginning 6 months after publication and ending 5 years after publication.

Data will be shared with researchers who provide a methodologically sound proposal to achieve aims in the approved proposal. Proposals should be directed to sportmedizin@mh-hannover.de to gain access, data requestors will need to sign a data-use agreement.