Title: Outline the benefits of an Exercise programme for people with Cystic Fibrosis and discuss the factors which may influence Exercise compliance.

Introduction
Cystic fibrosis (CF) is one of the most common and life limiting autosmal recessively inherited diseases in the world with an estimated occurrence in newborns of 1 per 3000 per annum (Walters, 2007). The majority of people with this disease are diagnosed during their first year of life with many countries now employing newborn screening programs. The basic mechanism of the disease consists of manifestation as pancreatic insufficiency leading to malabsorbtion and failure to thrive and impaired mucocillary clearance leading to reoccurring chest infections and bronchiestasis (Savage et al. 2011). With the recent advances in treatment of CF which have resulted in increased life span and survival rates, individuals can now expect to live into their fourth decade. Stats from the UK show that CF affects over 9000 people with 4000 under the age of 16 (Williams and Stevens, 2013). Irish stats show a similar pattern where 1200 individuals suffer from CF with 45% being under the age of 18. According to the CF trust (2010) the primary cause of death in individuals with CF is respiratory failure. CF is a progressive respiratory disease which results in an abnormal ventilator response to exercise for individuals with CF (Bradley and Moran, 2008). This contributes to dyspnoea which is a shortness of breath and is a major limiting factor to exercise tolerance in people with CF (O’ Neill, 1987). These exercise limits can add to compliance issues which will be discussed in further detail in later sections. Even though there is clear limiting factors to the benefits of exercise for the treatment of CF, Williams and Stevens (2013) report that rehabilitative exercise programmes form an important component of treatment and long term exercise programmes are considered positive treatment strategies. What this essay aims to discuss is the benefits of an exercise program for the treatment of CF along with the specific components of the most effective exercise intervention with support from the literature. Compliance issues will also be discussed in detail and how these issues can be minimised.
Search Strategies
Specific search strategies have been employed throughout this essay to find the most up to date relevant literature. The databases used consisted of Medline, the Cochrane Database of Systemic Reviews and Science Direct. Initial searches were carried out using the term ‘cystic fibrosis’ and then narrowed down using the key words ‘exercise’, ‘exercise intervention’, ‘review’, ‘training’, and ‘compliance’. Searches took place on 18/3/14, 19/3/14 and 20/3/2014. Filters including using ‘title, abstract, keywords’ with 20 papers per page. Medline returned 7137 papers while the Cochrane database returned 152 papers.
Benefits of an Exercise Program
There are many studies in the literature that advocate the benefit of physical activity as a treatment for CF. Participation in physical activity (PA) and exercise is encouraged in the treatment of CF (Simon, 2004). This is because participation in PA awards many health benefits including enhanced clearance of pulmonarysecretions (Bradley and Moran, 2008; Dwyer, 2011). Bradley and Moran also found that PA can lead to increased blood glucose control and bone mineral accretion. In addition to this Schneiderman-walker, 2005; Hebestreit, 2006; and Troosters 2009 all reported that with an increase in PA comes possible health benefits such as an increased exercise capacity, respiratory function and a better quality of life. These benefits are all associated with improved prognostic outcomes in CF.. Williams and Stevens (2013) report that maintaining or improving pulmonary function and aerobic capacity, and slowing down the annual rate of decline in forced expiratory volume (FEV) and VO2max is important as both are strong predictors of survival for children with CF. Therefore, any intervention that can impact positively on these health outcomes would be of potential benefit to patient prognosis and life span. The following studies have the same selection criteria which is as follows: subjects were all aged 6-18 years and all diagnosed with CF; exercise program lasted at least 2 weeks; methods are fully repeatable; randomised grouping of control and exercise groups. Selvaduri et al. (2002) reported that after a 19 day exercise program patients showed increased FEV as a result of aerobic and resistance training. They also reported that individuals showed an increased VO2max. Sosa et al. (2012) conducted an 8 week exercise program consisting of circuit, weight and aerobic training. Results showed improvements in VO2max, max bench press, leg press and seated row. However Sosa and colleagues observed no significant changes in pulmonary function, BMI, fat free mass or body mass. From the literature it is clear that there are many health related benefits for CF patients through the use of exercise programs. However there is a lack of constancy between the studies as the type, frequency, intensity and duration of exercise and therefore it is difficult to draw a consistent overall conclusion for the optimal exercise program. We can now begin to discuss the main components involved in the most effective form of exercise for the treatment of CF.
Components
For patients with CF their response to an exercise program can differ. This variability depends on the severity of the disease, their exercise capacity, VO2max and respiratory function. Cox et al. (2013) states that before any CF patient undergoes an exercise program they should be monitored for their exercise tolerance, physical abilities and whether or not they require oxygen supplementation. From the previously discussed studies it is seen that there is some good evidence that pulmonary function, exercise capacity and muscular strength can be improved through participation in PA. Selvaduri et al. (2002) showed great promise in their study for the use of exercise as a treatment where through the use of aerobic and resistance training resulted in significant improvements in pulmonary function, aerobic fitness and muscular strength within the exercise group.
Type
Klijn et al. (2004) has brought forward evidence to support the the use of anaerobic training methods for patients suffering from CF. Results showed that through anaerobic training, VO2 max and anaerobic power were both significantly improved. However most of the evidence seems to suggest that aerobic and resistance training seem to yield the best results. Schneiderman-Walker et al. (2005) found that after a 3 year aerobic training program there was a slowed decline of the forced vital capacity (FVC) amongst the patients. In addition Orenstein et al. (2004) who used both resistance and aerobic training found that muscle strength was significantly improved with pulmonary function being maintained. This is very important evidence to aid the reduction of the rate of decline of pulmonary function which is one of the main causes of death amongst CF sufferers. Most of the studies mentioned previous included leg strength training which all resulted in increased leg strength in the patients. This is important because according to Nixon et al. (1992) CF is characterised by pancreatic insufficiency and malabsorption of nutrients, causing a reduction fat and muscle mass. Exercise training programmes, that can improve muscular strength and size, will not only improve the functional capacity a CF patient, but have been shown to correlate strongly with an improved prognosis. So from this evidence it would seem that aerobic and resistance training both seem to have positive effects but still more research is needed as to which one works best or if a mixture of both is more desirable.
Frequency
According to Williams and Stevens (2013), there is currently not enough detailed physiological information to prescribe programmes of sufficient duration, intensity and frequency. However, from our scientific knowledge and the ACSM guidelines we know that patients suffering from severe CF need rest between exercise days. 3-4 days a week with rest between each day should suffice. It is interesting to note that McArdle (2001) found that after stopping exercise there is usually a drop of 1% exercise capacity per day seven days after stopping exercise so adherence is vital.
Intensity
As stated earlier more research is needed on what frequency, intensity and duration is optimal. However Schneiderman-Walker (2000), Selvaduri (2002), Klijn et al. (2004) and Orenstein et al. (2004) all used intensities for the aerobic exercise of 70-80% with weights used being 70-80% of 1 rep max also. The results of these studies of shown positive health benefits therefore it is feasible to use the same intensity they used.

Duration
According to ACSM a healthy individual should exercise for at least 30-45mins per day at a moderate intensity. However as CF patients are usually not able for these session lengths, exercise should start at 5mins perday for the first 2 weeks and then gradually build it up week after week depending on the length of the program. Similar to what was mentioned earlier there is no definite measure on how long the exercise session or program should last. From the studies mentioned in this essay each intervention lasted at least 2 weeks but vary in length up to 3 years. Recommendations show that if there is no adherence to the exercise program then symptoms could worsen ultimately having a detrimental effect on the patient’s prognosis. Therefore I would recommend that exercise programs should be conducted on an ongoing basis where adherence is the key component.
Compliance Issues
In the previous sections it was discussed about the many benefits of exercise to CF patients and that adherence is the key to increasing the patient’s life span. For people with CF the ability to participate in regular physical activity can be hampered by factors such as the environment (natural and built), financial cost and emotional and psychological barriers (Rimmer, 2004). These barriers contribute to people with chronic illness being less likely to report participation in moderate and vigorous physical activity compared to healthy populations (Marcus, 2000). Kettler et al.(2002) raised the worry that there is a growing concern for medical teams of the issue of patient compliance to prescribed health management and exercise plans. Having a family member who suffers from CF can be of great hardship to the family. Scneiderman-Walker (2000) found that if the patients enjoy the type of exercise and are actively engaged then they are more likely to comply to the exercise. It is also ideal if exercise and PA can be included in the individual’s everyday life. Habitual physical activity implies the performance of physical activity within the context of regular daily life (Clanchy, 2011) therefore it would be ideal for this to be included in the patients exercise program..

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