Nov 22, 2022

Exercise and Strength Training in Lung Transplant Patients

For patients with end-stage lung disease, lung transplantation (LTx) may increase survival and, importantly, a patient’s quality of life. Worldwide, the median survival time after LTx is 6.2 years (8.3 years if the recipient survives the first year), representing an increase from decades past. Improvements in perioperative care have contributed substantially to these developments, as have new insights into best practices surrounding physical therapy and rehabilitation.1 In addition to ongoing medical care, exercise and strength training are crucial for lung transplant patients. 

After lung transplant, patients frequently display exercise intolerance, with peak exercise remaining at 40% to 60% of predicted values even up to two years post-LTx. Limitations on exercise may be a result of pulmonary, cardiac, or musculoskeletal factors, with the muscular limitations playing a significant role.2,3 Poor oxygen extraction related to skeletal muscle dysfunction, especially in the lower limbs, has been hypothesized as the predominating limitation to exercise capacity – transplanted lungs may have a reduced ability to exchange gases and supply the body with oxygen.2 Pre-transplant chronic muscle dysfunction and deconditioning are also at play, as many patients who need lung transplants would have had decreasing abilities to exercise due to their conditions.4 Thus, physical therapy is an important component of both the pre- and post-operative period to provide exercise and strength training to lung transplant patients. 

During the pre-operative period, exercise training can reduce muscular deconditioning and improve quality of life after the lung transplant.5 In one study, researchers found that in 345 candidates for lung transplant, a 2.6-day decrease in overall hospitalization times was associated with each 100-meter increase in a patient’s six-minute walking test (6MWT) results, a test commonly used to evaluate exercise capacity.6  

While no formal guidelines for pre-transplant exercise training exist, various studies have emphasized the importance of progressive aerobic exercise and strengthening of the upper and lower extremities two to three days per week for at least six to eight weeks, with close surveillance of a patient’s symptoms and oxygenation as needed during exercise. In LTx candidates, muscle function in the limbs is reduced; quadricep strength (most commonly tested in research studies) may be 49%-86% of otherwise expected values.7 Given the breathing limitations of LTx patients, exercise modalities such as interval training and one-legged exercise may be ideal for promoting optimal muscle stimulation in the limbs.5 

Physical therapy after lung transplantation generally follows established protocols, which may vary across institutions. Postoperative rehabilitation begins in the hospital, with range-of-motion, ambulation, cough/mucociliary clearance, and thoracic mobility exercises. Outpatient programs include cardiopulmonary conditioning, often through a progressive walking regimen. 6MWT results are monitored regularly in post-transplant rehabilitation programs. Strength training and flexibility is emphasized as well. Lower extremity rehabilitation may include supine knee-to-chest exercises, hip abduction/adduction exercises, angle pumps, etc., and upper extremity rehabilitation may include free-weight and resistance exercises. Postural exercise for the neck and shoulder are also an important component of rehabilitation in lung transplant patients.7,8,9 

With 4,600 patients undergoing LTx each year, comprehensive rehabilitation programs continue to be of great importance. Researchers are pursuing innovative work to improve these programs, with new programs conducted remotely (telerehabilitation) to reduce risks of infection in this vulnerable patient population. “At-home” care may be conducive to patterns of intermittent clinical supervision that facilitate better adherence to self-managed exercise programs, and ultimately better exercise habits after formal rehabilitation programs end.10 

References 

  1. van der Mark SC, Hoek RAS, Hellemons ME. Developments in lung transplantation over the past decade. Eur Respir Rev. 2020;29(157):190132. doi:10.1183/16000617.0132-2019 
  1. Braccioni F, Bottigliengo D, Ermolao A, et al. Dyspnea, effort and muscle pain during exercise in lung transplant recipients: an analysis of their association with cardiopulmonary function parameters using machine learning. Respir Res. 2020;21(1):267. doi:10.1186/s12931-020-01535-5 
  1. Mathur S, Reid WD, Levy RD. Exercise limitation in recipients of lung transplants. Phys Ther. 2004;84:1178–1187. doi:10.1093/ptj/84.12.1178 
  1. Dudley KA, El-Chemaly S. Cardiopulmonary exercise testing in lung transplantation: a review. Pulm Med. 2012;2012:237852. doi:10.1155/2012/237852 
  1. Langer D. Rehabilitation in patients before and after lung transplantation. Respiration. 2015;89(5):353-362. doi:10.1159/000430451 
  1. Li M, Mathur S, Chowdhury NA, Helm D, Singer LG: Pulmonary rehabilitation in lung transplant candidates. J Heart Lung Transplant 2013;32:626-632. 
  1. Wickerson L, Rozenberg D, Janaudis-Ferreira T, et al. Physical rehabilitation for lung transplant candidates and recipients: An evidence-informed clinical approach. World J Transplant. 2016;6(3):517-531. doi:10.5500/wjt.v6.i3.517 
  1. Downs AM. Physical therapy in lung transplantation. Phys Ther. 1996;76(6):626-642. doi:10.1093/ptj/76.6.626 
  1. Candemir I, Ergun P, Kaymaz D, et al. The Efficacy of Outpatient Pulmonary Rehabilitation After Bilateral Lung Transplantation. J Cardiopulm Rehabil Prev. 2019;39(4):E7-E12. doi:10.1097/HCR.0000000000000391 
  1. Choi J, Hergenroeder AL, Burke L, et al. Delivering an in-home exercise program via telerehabilitation: A pilot study of Lung Transplant Go (LTGO). Int J Telerehabil. 2016;8(2):15-26. doi:10.5195/ijt.2016.6201