A.R. Morris

ePS04.7 A survey of activity levels and sedentary time in adult CF patients

36% of the control group. With regard to strategies to decrease barriers 75% of CF patients “think about the advantage of sport” compared to 82% in the control group. Conclusion: Physical barriers were more important for healthy than for CF patients. Despite time consuming treatment CF patients do not regard “stress” more often as barrier than healthy volunteers. Concerning the barrier management the acute strategy to “think about the advantage of exercise” is important for both groups while others differ. The challenge for the individualized activity program is therefore to develop individual strategies to decrease barriers and identify facilitators to promote physical activity for CF patients.

WS21.5 The use of serum creatinine to estimate skeletal muscle mass in cystic fibrosis

Objectives A lack of skeletal muscle mass is associated with an increase in mortality amongst people with cystic fibrosis (CF). Serum creatinine can be used as a surrogate marker of muscle mass in people with normal renal function and under steady state conditions. The aim of the current study was to investigate the feasibility of using creatinine to estimate muscle mass in CF patients with normal renal function and examine the potential impact of physical activity status. Methods The body composition of seventeen patients was assessed using leg-to-leg bioelectrical impedance. Physical activity status was estimated using the Global-Physical-Activity-Questionnaire. The Pearson correlation coefficient ( r ) was used to determine the strength of relationships between measures of body composition, levels of creatinine and physical activity status. Results Mean (±SD) body mass, muscle mass and body fat was reported at 63.8±13.7 kg, 48.3±9.0 kg and 19.5±9.4% respectively. Muscle mass showed a strong and positive correlation to creatinine ( r = 0.81, p r = –0.69, p Conclusion Creatinine is a good indicator of skeletal muscle mass in patients with CF and represents a useful biomarker in the assessment of nutritional status. Patients who present with low creatinine may be attributed to a depletion in the relative proportion of muscle mass. The amount of time spent being sedentary each week seems, to a greater degree, determine skeletal muscle mass.

WS14.2 Assessing components of fitness in cystic fibrosis: The practicality and value of using a battery of exercise tests in CF clinical practice

WS14.1 Evaluation of physical activity using the habitual activity estimation scale (HAES) questionnaire in a multicenter study N. Alarie1, J.L. Agnew2, M.P. McIlwaine3, F. Ratjen4, G.F. Davidson5, R. Milner6, L.C. Lands7. 1McGill University Health Center Research Institute, Montreal Children’s Hospital, Allied Health Services, Physiotherapy Department, Montreal, Canada; 2Sick Kids Research Institute, Hospital for Sick Children, Division of Respiratory Medicine and Department of Rehabilitation Sciences, Toronto, Canada; 3BC Children’s Hospital, Division of Paediatric Respirology, Vancouver, Canada; 4Sick Kids Research Institute, Hospital for Sick Children, and University of Toronto, Division of Respiratory Medicine, Department of Paediatrics and Program in Physiology and Experimental Medicine, Toronto, Canada; 5BC Children’s Hospital, Cystic Fibrosis Clinic, Division of Pediatrics, Vancouver, Canada; 6University of British Columbia, Child and Family Research Institute, Vancouver, Canada; 7McGill University Health Center Research Institute, Montreal Children’s Hospital, Division of Paediatric Respiratory Medicine, Montreal, Canada

248* Using an individualized treadmill protocol to assess maximal steady state exercise capacity in cystic fibrosis

Introduction: Although the 6 minute walk test (6 MWT) is an established, safe and well tolerated method of assessing sub-maximal exercise capacity in CF, it requires adequate space and may not easily represent activities of daily living. We therefore examined the utility of a simple individualized treadmill protocol to assess metabolic capacity, using the maximal steady state (MSS) and compared it with the 6 MWT. Patients and Methods: Paired tests were carried out on 216 adult CF patients (mean age 25 years, 106 male): MSS treadmill capacity was compared with a 6 MWT around a 20 metre course. Patients warmed up for 3 minutes at a comfortable pace before using a combination of speed and incline to incrementally reach their highest sustainable exercise intensity, without experiencing undue fatigue and without encouragement, for a minimum of 6 minutes. ACSM metabolic equations were used to estimate O2 cost and calculate a metabolic equivalent (MET) value for the exercise. Results: There was a strong correlation between MSS MET values and 6MWT scores (r2 = 0.83, P< 0.0001). Furthermore, those who were only able to sustain a low steady state on the treadmill were better able to replicate and frequently surpass their efforts on the 6MWT. Patients achieving higher steady state intensity are likely to have been hindered by the increased anaerobic demands of slowing and reversing direction every 20 metres. Conclusions: The use of a simple sub-maximal treadmill test may aid clinicians to better relate a patient’s functional capacity to the demands of leisure, occupation and daily living as well as to help chart changes in physical fitness and clinical status.