It is well established that heart transplantation improves patients' quality of life, exercise capacity, and survival. However, exercise capacity after a heart transplant still remains subnormal (1).Exercise training is a very important intervention for heart transplant recipients. It improves exercise tolerance, quality of life, and cardiac reinnervation. High-intensity interval exercise training has appeared in the literature as a safe and efficient method to improve exercise capacity in patients with coronary artery disease and in patients with heart failure (2,3).The study by Nytrøen et al. (4) is very interesting and adds important information to what we know about exercise training in heart transplant recipients. This randomized clinical trial investigated the effects of high-intensity interval exercise training in peak VO 2 and peripheral muscle strength. The main finding of this study (4) was that high-interval training was safe, applicable and effective in improving peak VO 2 and muscular exercise capacity.It is important to point out that this study (4) used an unusual and ambitious interval exercise training protocol. The sessions consisted of a 10-minute warm-up, followed by 4-minute exercise bouts at 85-95% of maximum heart rate, interposed by a 3-minute active recovery period. Most of the studies on interval exercise training in heart failure assume an overall recovery time greater than or equal to the period of high-intensity exercise. The protocol used in the study by Nytrøen et al. (4) opens a new discussion about which method of high-intensity interval exercise training is the most appropriate for cardiac patients, especially for heart transplant recipients. Moreover, it would be interesting to test the interval training in different phases of cardiac reinnervation (and cardiovascular control), once the studied patients had 4 years of transplantation and probably some important degree of reinnervation.Another important point to be discussed is the peak VO 2 improvement. The study by Nytrøen et al. (4) showed an 11.5% improvement after high-intensity interval training. However, a previous study showed a 25.9% improvement after continuous training (5). The lack of a control group performing continuous exercise training limits the interpretation of Nytrøen et al.'s study (4). So, the superiority of highintensity interval training for heart transplant recipients is not established.Thus, new trials are needed to elucidate if high-intensity interval training is superior to continuous training for VO 2 improvement. Moreover, it is important to investigate the best protocol of high-intensity interval training regarding recovery and exercise bouts in different years of heart transplant and cardiac reinnervation.

BACKGROUND: A living donor transplant improves the survival and quality of life of a transplant patient. However, the impact of transplantation on postoperative lung function and respiratory muscular strength in kidney donors remains unknown. OBJECTIVE: To evaluate pulmonary function, respiratory muscle strength, quality of life and the incidence of postoperative pulmonary complications (PPCs) in kidney donors undergoing nephrectomy. METHOD: This prospective cohort enrolled 110 consecutive kidney donors undergoing nephrectomy. Subjects underwent pulmonary function (using spirometry) and respiratory muscular strength (using manovacuometry) assessments on the day prior to surgery and 1, 2, 3 and 5 days postoperatively. Quality of life (measured by the SF-36) was evaluated preoperatively and 30 days postoperatively. PPCs were assessed daily by a blinded assessor. RESULTS: Donors exhibited a decrease of 27% in forced vital capacity, 58% in maximum inspiratory capacity and 51% in maximum expiratory pressure on the 1stpostoperative day (p<0.001) but this improved over days 2, 3 and 5 but had not returned to preoperative levels. Patient quality of life was still impaired at 30 days with regards to functional capacity, physical role, pain, vitality and social functioning (p<0.05) but these parameters improved slowly. None of the patients developed PPCs. CONCLUSION: Kidney donors submitted to nephrectomy exhibited a reduction in pulmonary function, respiratory muscular strength and quality of life, most of which were improving toward pre-surgical levels.