Feasibility of higher intensity exercise in patients with chronic kidney disease

BACKGROUND: Higher intensity exercise is a more effective way of evoking improvements in cardiorespiratory fitness in many chronic disease populations compared to moderate intensity continuous training. The aim of this study was to investigate the feasibility of participation in higher intensity exercise in patients with chronic kidney disease (CKD).
METHODS: This study is an observational sub-study of the intervention arm of a randomized control trial. Forty-four participants with stage 3-4 CKD in the intervention arm were required to complete a predominantly home-based 12 month individualized exercise intervention. Physical activity levels, exercise capacity (METs) and blood biochemistry were measured at baseline and 12 months. The physical activity groups (higher intensity, moderate intensity and not meeting guidelines) were determined from the six months activity prior to the 12 month testing visit.
RESULTS: At 12 months, the number of patients who reported performing weekly higher intensity exercise in the previous six months of the intervention increased by 23%. Participants completing higher intensity exercise had a significantly greater exercise capacity at 12 months (11.9±3.7 METs) than participants reporting moderate intensity exercise and those not meeting guidelines (9.2±1.7, 7.6±3.2 METs). Hemoglobin levels and exercise capacity were significantly higher at baseline in patients who reported exercising at higher intensities (142.9±16.1 g/L and 9.8±4.2 METs) compared to those reporting moderate intensity exercise (129.8±12.9 g/L and 8±3.1 METs) and not meeting guidelines (127.3±12.5 g/L and 6±2 METs).
CONCLUSIONS: The study was successful in increasing higher intensity physical activity in a large proportion of patients with CKD.