1. Redelmeier DA , Bayoumi AM , Goldstein RS et al. Interpreting small differences in functional status: the six minute walk test in chronic lung disease patients . Am J Respir Crit Care Med1997; 155: 1278-1282 .
2.
2. Guyatt GH , Berman LB , Townsend M et al. A measure of quality of life for clinical trials in chronic lung disease . Thorax1987; 42: 773-778 .
3.
3. Pulmonary rehabilitation: British Thoracic Society Statement . Thorax2001; 56: 827-834 .
4.
4. Coppoolse R , Schols AMWJ , Baarends EM et al. Interval versus continuous training in patients with severe COPD: a randomised clinical trial . Eur Respir J1999; 14: 258-263 .
5.
5. Vogiatzis I , Nanas S , Roussos C . Interval training as an altemative modality to continuous exercise in patients with COPD . Eur Respir J2002; 20: 12-19 .
6.
6. Clark CJ , Cochrane L , Mackay E . Low intensity peripheral muscle conditioning improves exercise tolerence and breathlessness in COPD . Eur Respir J1996; 9: 2590-2596 .
7.
7. Normandin EA , McCusker C , Conners M et al. An evaluation of two approaches to exercise conditioning in pulmonary rehabilitation . Chest2002; 121: 1085-1091 .
