The AlterG®-anti-gravity treadmill provides lower body weight support which enables individuals to exercise without feeling their full body weight. How this body weight support influences cardiovascular, respiratory, vascular and metabolic parameters is currently unclear. Further, whether body weight support influences the trainability in response to moderate continuous exercise is unknown. This investigation has two main goals. First, we explore the direct influence of lower body weight support on cardiometabolic parameters during maximal exercise testing. Second, we aim to compare changes in cardiorespiratory fitness in response to a structured exercise protocol using moderate intensity with and without lower body weight support.

Inclusion Criteria:

• maximal oxygen consumption below age-sex specific standard

Exclusion Criteria:

• acute infection within the last four weeks
• anemia (males: Hb < 8.1 mmol/L; females Hb < 7.4 mmol/L)
• previous reports of myo-, endo, or pericarditis
• previous stroke or acute myocardial infarction
• heart failure (NYHA > 1)
• aortic valve stenosis
• congenital heart disease
• cardiomyopathy
• severe left ventricular hypertrophy
• cardiac arrythmias
• hypertension
• diabetes
• BMI > 35
• cancer
• pregnancy
• aneurysm of aorta or cerebral arteries