Feasibility of a New Model for Exercise Prescription Combined With Behavior Modification in Cystic Fibrosis

During the hospitalization (T0 to T1; Figure 1, next page), participants will perform supervised exercise 6 days/wk. On each of these days, there will be a 5-10 min warm up consisting of low intensity execises for lower and upper exermity muscles. The total time per week will be between 2.5 and 3.5 hours.

Three days/wk will consist of aerobic exercise ("frequency"). The various "modes (types)" for this exercise include 1) overground ambulation (including stairs), 2) treadmill ambulation, 3) stationary cycling, or 4) repetitive body-weight exercises (e.g., "jumping jacks"). The "time (duration)" of these sessions will be 20-30 min/day. The "intensity" will be moderate (40-60% of heart rate reserve and/or perceived dyspnea/exertion of 3-5) to vigogous (60-85% of heart rate reserve and/or perceived dyspnea/exertion of 6-8). Participants will be given a HR monitor and specific "target" HR ranges based on their resting HR in standing and their age predicted maximal HR (NOTE: maximal exercise testing will not be performed); they will also be familiarized and instructed in use of the Borg CR10 scale to rate perceived dyspnea/exertion Participants should be able to "talk comfortably" during moderate intensity exercise, while talking should be "somewhat challenging" during vigorous efforts; HR, as well as perceived exertion/dyspnea and "talk test" will be monitored throughout each supervised session by trained personnel.

On alternate days, participants will perform supervised resistance exercise training (3 days/wk; "frequency"). The various "modes (types)" for this exercise include 1) body-weight exercises (e.g., lunges, squats, jumping, situps, pushups) and/or 2) resistance bands and dumbbells; exercises will target upper extremity, trunk/core, and lower extremity muscles (NOTE: specific inspiratory muscle training will not be performed). The "intensity" of these exercises will be at approximately 12-15 repetition max (that is, on the 3rd set of an exercise, the participant should have difficulty performing more than 12-15 quality (good form) repetitions of the exercise. An appropriate number of exercises will be selected such that the exercise "duration (time)" will be 20-30 min/day.