Exercise as it relates to Disease/Physical exercise as an additional therapy for sleep apnea

What is the Background to this research?
Sleep apnea is a detrimental medical condition, which effects around 9% of women and 25% of men within Australia 2018 while many Australian’s still remain undiagnosed or untreated. Sleep apnea is caused by the complete or partial blockage of the throat while sleeping (the tongue falls back blocking the airway) .The partial stoppage of breathing is called hypopnea while the total blockage to stop breathing is called apnea These moments of blockage can occur multiple (hundreds) times per night. While the throat is restricting the air flow, this effects the body by preventing the lungs to take in the needed oxygen, therefore increasing carbon dioxide within the body, transferring this into the blood, and body systems. This causes the body to jolt awake, creating a fresh inflow of air that the body needs, but in doing this, the body is being woken more times then recommended (causing a lack of sleep).

Symptoms of sleep apnea include: snoring, waking suddenly during the night, morning headaches, feeling tired and needing a nap during the day, irritability, increased urination during the night and waking feeling tired If sleep apnea remains untreated, there can potentially be various other negative health conditions/effects occur .Some of these conditions include: risk of cardiovascular disease (CVD), diabetes (metabolic disease), stroke, depression .Sleep apnea can be the cause of sudden death during sleep.

Certain factors of individuals health or lifestyle can put them at a bigger risk of developing sleep apnea. It is a higher risk for males and is also a bigger risk as age increases (large increase above 65yrs) Other lifestyle or genetic factors include: obesity, family history, smoking or alcohol use, current CVD or diabetes along with anatomical differences.

Sleep apnea can come in different levels of severity. This can range from normal through to severe sleep apnea. This is dependent on the rate of breathing being stopped or partially restricted. This is counted of their RDI level during sleep (respiratory disturbance index). Treating sleep apnea can lower mortality rate, decreased risk of developing a CVD or type 2 diabetes and everyday health.

Where is this research from?
This research was conducted by a few authors for a volume of ‘Sleeping and Breathing’ (volume 4). Assisted by the Department of Sports Medicine and Preventative Medicine at the University if Freiburg and the University of Ulm.

What kind of research was this?
This research was an open trial for qualitative research to discover if exercise is a possible aid towards sleep apnea.

What did this research involve?
This research was conducted over a 6 month period involving 1 female and 10 males. These patients had all been diagnosed with moderate to severe sleep apnea. Along with having no cardiovascular disease risk. The 11 patients were treated with the use of Nasal CPAP (this assists breathing during sleep and currently in the main treatment for sleep apnea), three months prior to the research starting. During the 6 months, they were given supervised exercise to complete each week (2 hours total per week) of a mild to moderate exercise prescription.
 * Moderate to serve sleep apnea is defined at 15 to 30 ‘apneas’per hour (times being woken by the apnea events during the night).

Before they started there were baseline measures taken which included:
 * Polysomnography without CPAP (this records brain waves, oxygen saturation in blood, HR and breathing rate)
 * ‘Bicycle exercise test’ including a lactate test during
 * Echocardiogram (sonogram of the heart)
 * Weight and height

What were the basic results?
This research concluded that the end result of mild to moderate exercise of two hours per week that, the following had recorded changes:

Along with these changes, the following listed had NO significant change:
 * Height
 * Lactate Profile
 * Parameters for exercise performance
 * Blood Pressure
 * Oxygen Saturation

Meanings: RDI= respiratory disturbance index, SaO2 mean= Mean of the oxygen saturation in arterial blood - haemoglobin (amount of oxygen in blood), saO2 min = Oxygen saturation at lowest, REM sleep phase= Rapid Eye Movement during sleep - deep sleep (this is important for good sleep), Lactate profiles= Indicator of fatigue in muscles, Blood pressure= Force and rate of blood flow (SBP and DBP), Parameters= physical exertion during exercise,

So what does this mean?
As explained in "sleeping and breathing" there overall was not a great impact of 2 hours of mild to moderate intensity exercise on assisting as an additional therapy for sleep apnea. The exercise will benefit the individual through indirect matters rather then being a direct benefit to the condition. Such as: can cause weight loss which in turn will benefit sleep apnea, along with benefits to the circulatory and respiratory system as a whole. From the results explained above, the greatest benefit towards sleep apnea from exercise came from; the decrease in RDI (30%).

Is this research valid?
All patients used in this study were not a risk to further medical complications, therefore if there is was benefit in the exercise undertaken for sleep apnea, it would be clear and not hindered through potential complications (as they were pre tested with an echocardiogram). The study was also taken, with many pre tests and potential indicators - showing a large variety of possible changes.

The study was performed by University's and Departments of Medicine therefore meaning they do have a good rapport and can be reliable for information.

What conclusions can we take from this research?
Exercise has the potential to be of great benefit to assist in the treatment of sleep apnea. Mild to moderate exercise does not directly assist sleep apnea but rather can help other measures that do NOT directly impact (general health will improve). Although this does not mean that vigorous activity could not be a potential benefit to treatment. It was shown to assist in respiratory disturbance index (RDI) which is useful for a better sleep, as the main benefit.

Potential Implications of Research Article
This research has some potential implications in the way it has been presented. The main focus is on the negative side of possible effects rather then on what benefit could be taken from it. Such as: it highlights the areas of the study were there was 'no significant change', whereas it would be uplifting to see some of the benefits as well. This way it can influence the reader to keep a clear frame of mind towards exercise and sleep apnea rather than listing why not to be physically active. This research could have also been improved with the use of a greater variety in the patients used, i.e. some without use of CPAP prior, some with mild to moderate sleep apnea or patients taking part in a higher exercise load per week. This way it could highlight at what point (of sleep apnea and exercise), that physical activity becomes effective.

Practical Advice
Practical advice to be taken from this research is that there is always benefit and negatives to exercise, but in this research there was either no change or a positive change, therefore it could potentially be helpful in the assistance of sleep apnea. There is only some variables shown in this study, whereas others (higher intensity of exercise or higher amount) may be of benefit.

Further information/resources:
Further Reading: Effects of Exercise on training on Sleep Apnea - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4216726/

Further Reading: CPAP and Exercise - https://www.usa.philips.com/c-m-hs/better-sleep-breathing-blog/better-sleep/cpap-and-exercise-equals

Regular physical exercise: evidence for health benefits in OSA patients?: https://link.springer.com/article/10.1007/s11325-013-0808-5