East Dallas Chiropractor Best Practices
Research Commentary;
Exercise and Sleep Apnea
A review of
Christopher E. Kline, E. Patrick Crowley, Gary B. Ewing, James B. Burch, Steven N. Blair, J. Larry Durstine, J. Mark Davis, Shawn D. Youngstedt, The Effect of Exercise Training on Obstructive Sleep Apnea and Sleep Quality: A Randomized Controlled Trial, Sleep, Volume 34, Issue 12, 1 December 2011, Pages 1631–1640, doi.org/10.5665/sleep.1422
By Dr. Trenton Yeomans
Summarized Review Conclusions
In this study they found that after a 12-week exercise program for participants who were diagnosed with moderate or a higher severity of obstructive sleep apnea they saw significant improvements in apnea events while sleeping through the night and significant improvements of oxygen desaturation index (ODI). This means that the patients were experiencing less decreases in the amount of oxygen their body had while sleeping throughout the night and had a decrease of apnea events where they would hold their breath. This study shows that exercise is a great tool when it comes to managing obstructive sleep apnea and if you are somebody who struggles with this, getting out and doing moderate aerobic exercise at least 120-150 minutes a week you can also get the benefits of sleeping better and managing obstructive sleep apnea.
“Obstructive sleep apnea (OSA) is a prevalent sleep disorder, affecting up to 15% of the population. If left untreated, OSA has potentially severe health consequences, such as cognitive impairment, cardiovascular disease, diabetes, and early mortality.”
Christopher E. Kline, E. Patrick Crowley, Gary B. Ewing, James B. Burch, Steven N. Blair, J. Larry Durstine, J. Mark Davis, Shawn D. Youngstedt, The Effect of Exercise Training on Obstructive Sleep Apnea and Sleep Quality: A Randomized Controlled Trial, Sleep, Volume 34, Issue 12, 1 December 2011, Pages 1631–1640, doi.org/10.5665/sleep.1422
“Although weight loss is the most obvious plausible mediator explaining how exercise may reduce OSA severity, decreases in AHI(Apnea-hypopnea Index following exercise training have been found to be independent of changes in body weight in the limited epidemiologic and experimental studies that have examined this hypothesis.”
Christopher E. Kline, E. Patrick Crowley, Gary B. Ewing, James B. Burch, Steven N. Blair, J. Larry Durstine, J. Mark Davis, Shawn D. Youngstedt, The Effect of Exercise Training on Obstructive Sleep Apnea and Sleep Quality: A Randomized Controlled Trial, Sleep, Volume 34, Issue 12, 1 December 2011, Pages 1631–1640,doi.org/10.5665/sleep.1422
“In conclusion, this study found that exercise training resulted in a modest reduction in AHI despite minimal change in body weight. Moderate improvements in objective and subjective sleep quality also occurred following exercise training. The results suggest that exercise training exerts a significant effect on OSA severity and sleep quality, and that exercise training may provide benefit for the management of OSA beyond that of solely facilitating weight loss.”
Christopher E. Kline, E. Patrick Crowley, Gary B. Ewing, James B. Burch, Steven N. Blair, J. Larry Durstine, J. Mark Davis, Shawn D. Youngstedt, The Effect of Exercise Training on Obstructive Sleep Apnea and Sleep Quality: A Randomized Controlled Trial, Sleep, Volume 34, Issue 12, 1 December 2011, Pages 1631–1640, doi.org/10.5665/sleep.1422
Introduction to the Research
This research was done to investigate the effect of exercise training on obstructive sleep apnea and the quality of sleep. Measurements that were tracked are Oxygen desaturation index (ODI) and Apnea-Hypopnea Index (AHI). They tracked the participants over a 12-week exercise program where they did 120-150 minutes of moderate aerobic exercise a week and 2 days of resistance training exercise. The results showed that regardless of weight loss patients not only experienced less apnea events, but they also had a better quality of sleep. I enjoyed this research because it again shows how important it is to exercise. As somebody who has obstructive sleep apnea, I always make sure I exercise for my health and I am always looking for different ways to improve my health to keep me out of pain and improve my sleep and recovery.
Research Methodology
Participants
Adults ages 18-55 years with at least moderate-severity OSA (AHI ≥ 15 at screening) who were overweight/obese (body mass index ≥ 25), sedentary (< 2 exercise sessions/week), at stable (> 3 mo) medication doses (e.g., antihypertensives, antidepressants), not currently being treated for OSA and not actively attempting to lose weight were eligible for participation. Exclusion criteria included known or suspected significant cardiovascular, pulmonary, or metabolic disease; uncontrolled hypertension (> 159/99 mm Hg); pregnancy; and inability to exercise due to orthopedic or musculoskeletal problems.
Recruitment, Screening, and Timeline
Individuals were recruited from local sleep clinics and from the general population via media advertisements. Following an initial phone screen, individuals were mailed additional screening materials, including the Berlin Questionnaire.22 Individuals who were previously diagnosed with OSA or classified as “high risk” for OSA based on the Berlin Questionnaire and otherwise eligible were invited to the laboratory to further review the protocol. At the conclusion of the visit, participants provided written informed consent approved by the Institutional Review Boards of the University of South Carolina and the WJB Dorn VA Medical Center. Participants were then scheduled for one night of laboratory polysomnography (PSG) to further screen for OSA. Individuals with a screening AHI ≥ 15 were enrolled in the study.
Prior to baseline assessment, participants were required to meet with the study team on 2 occasions to become familiar with the research facility, practice study procedures, and view a presentation on OSA (prevalence, pathophysiology, established treatment options). The primary purposes for these “run-in” visits were to educate the participants on OSA and to establish whether the participants were committed to participating in the study.
Individuals who completed the run-in visits were scheduled for 3 baseline assessments, which took place over a 7-10 day period. The assessments were conducted on separate days and consisted of: (1) a single night of laboratory PSG; (2) a laboratory assessment, in which body composition, pulmonary function, and respiratory muscle strength were assessed; (3) a physician-supervised graded exercise test to screen for possible adverse responses to exercise. Throughout this period, participants continuously wore a wrist actigraph to monitor sleep at home.
Once baseline assessments were complete, participants were randomized to either a 12-week exercise training or stretching control treatment. Following completion of the intervention, participants completed the same assessments as at baseline following a day without exercise. Participants were compensated $300 for completion of the study.
Randomization
Following baseline, participants were randomly allocated to exercise and stretching control treatments by a 3:2 ratio, respectively. Randomization was stratified by sex and screening AHI (15-30 or > 30) in blocks of 5, using a computer-generated randomization list (SAS v. 9.2, SAS Institute, Cary, NC). Treatment allocations were prepared by an individual otherwise unaffiliated with the study and placed in sealed opaque envelopes.
Although participants could not be blinded to their treatment, both programs were presented as active treatments. To assess treatment expectancy, participants completed a brief questionnaire following randomization that queried expected changes in OSA severity, sleep quality, daytime sleepiness, mood, and overall health, using 5-point Likert scales (1: much worse; 5: much better). In addition, participants were asked to rate their satisfaction with their randomized treatment (1: very dissatisfied; 5: very satisfied).
Treatments
Exercise training
Individuals assigned to the exercise training treatment met 4 times per week for 12 weeks. All exercise sessions were supervised by staff trained in exercise physiology. To limit the risk of injury, the exercise dose was gradually increased during the initial 4 weeks of training. For weeks 5-12, exercise dose was 150 min/week of aerobic exercise distributed over 4 sessions per week, followed on 2 days per week by resistance exercise consisting of 2 sets of 10-12 repetitions for 8 different exercises. The exercise dose was chosen to comply with public health physical activity recommendations.23 Aerobic training intensity was 60% of heart rate reserve (HRR), considered to be moderate intensity,24 and was continuously monitored with heart rate telemetry (FS2, Polar Electro Oy, Kempele, Finland). Each aerobic exercise session began with a 5-min warm-up and ended with a 5-min cool-down, which was not included in the prescribed duration. Treadmill exercise was the primary aerobic activity, though elliptical or bicycle ergometer exercise was permitted when necessary (e.g., when participants experienced lower leg soreness).
Resistance exercise, performed twice per week on nonconsecutive days, included shoulder press, lat pulldown, leg extension/leg flexion (alternated between sessions), chest press, upright row, leg press, bicep curls/triceps extension (alternated between sessions), and abdominal crunches. Resistance was increased when 12 repetitions could be performed on the second set with proper form.
Stretching control
Participants assigned to the stretching control treatment met 2 times per week for 12 weeks for supervised flexibility training sessions. At each visit, participants performed 2 sets of 12-15 stretches, each held for 15-30 s, which focused on whole body flexibility. Although no change in OSA severity was expected from this intervention, it was chosen to reduce the potential confound of interpersonal interaction on study outcomes.
Sleep Measures
Laboratory polysomnography
Single-night laboratory PSG (Alice 5, Philips Respironics, Murrysville, PA) was performed at screening, baseline, and post-intervention. Participants were prepared for recording with a standard PSG montage25 that included F4/M1, C4/M1, O4/M1 electroencephalograms (EEG), bilateral electroculograms, submentalis electromyogram (EMG), thoracic and abdominal respiratory inductance plethysmography, modified lead II electrocardiogram, body position sensor, and single-leg tibialis anterior EMG. Airflow was monitored with an oronasal thermistor and nasal cannula pressure transducer, and arterial oxyhemoglobin saturation (SpO2) was assessed with finger pulse oximetry (LNOP DCI, Masimo, Irvine, CA). Time in bed was fixed at 8 h and initiated according to the participant’s usual bedtime.
Sleep stage scoring was performed according to standard criteria25 by one registered PSG technician blinded to treatment assignment. An apnea was defined as ≥ 90% airflow reduction for ≥ 10 s, and a hypopnea was defined as ≥ 30% reduction in airflow accompanied by ≥ 4% desaturation from baseline. An arousal was defined as ≥ 3-s increase in EEG frequency following ≥ 10 s of stable sleep, accompanied by an increase in submentalis EMG activity for ≥ 1 s during REM sleep. The AHI was calculated as the number of apneas and hypopneas per hour of sleep, and was summarized by body position and sleep stage. The arousal index was calculated as the number of arousals per hour of sleep, and the oxygen desaturation index (ODI) was calculated as the number of SpO2 drops ≥ 4% per hour of sleep.
Objective home sleep
For approximately 7 days at baseline and again at post-intervention, participants wore an Actiwatch Spectrum actigraph (Philips Respironics, Bend, OR) on the non-dominant wrist to monitor home sleep/wake status. Participants wore the same actigraph at baseline and post-intervention. Participants were instructed to press an event marker to denote bedtime and out-of-bed time and at the initiation and end of daytime naps. Following data retrieval, individual records were inspected and edited (e.g., to set event markings as the start and end of rest intervals). Sleep/wake status was estimated with the Actiware software algorithm26 (v. 5.59.0015; Philips Respironics, Bend, OR) set to medium-threshold for wake detection and 5 immobile minutes for sleep onset and end.27 Sleep onset latency (SOL), total sleep time (TST), wakefulness after sleep onset (WASO), and sleep efficiency (SE) were obtained for analysis. In addition, a fragmentation index, a measurement of movement and restlessness, was calculated by the software algorithm. Due to an allergic skin reaction to the Actiwatch for one participant, 42 participants provided data for analysis. Values were averaged across all baseline and post-intervention nights for analyses.
Subjective sleep quality
The Pittsburgh Sleep Quality Index (PSQI)28 was administered at baseline and post-intervention prior to laboratory PSG to assess subjective sleep quality over the previous 2 weeks. Seven component scores were generated: sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbances, use of sleep medications, and daytime dysfunction. A global score between 0-21 was calculated from summing the subscale scores. Global scores > 5 have been considered to be indicative of poor sleep quality.28
Additional Measures
Assessment of lifestyle activity and eating habits
Participants were asked to maintain their normal lifestyle activity patterns and eating habits throughout the study. To monitor unsupervised activity, participants wore a piezoelectric pedometer (NL-1000, New Lifestyles Inc., Lees Summit, MO) from baseline through the end of post-intervention assessment. Participants removed the pedometer during the supervised activity sessions. The NL-1000 recorded daily steps and time spent in moderate- to vigorous-intensity activity (MVPA),29 and data were organized into 2-week bins for analysis.
Dietary habits were evaluated with the Rapid Eating Assessment for Participants-Short Version (REAP-S)30 at baseline and post-intervention. With the 13-item REAP-S, participants were asked to indicate how frequently they skipped breakfast, ate at restaurants, and ate various categories of food (e.g., processed meats, fried foods) using 3 response options (1 = rarely/never, 2 = sometimes, 3 = usually/often). The total score was derived by summing the scores of the 13 items.
Assessment of potential mediators of exercise training
Changes in body composition, pulmonary function, and respiratory muscle strength were explored as possible mediators between exercise training and improvement in AHI. These measures were taken in the morning following an overnight fast at baseline and within 5 days of completion of the 12-week intervention.
Body composition
Height and weight were measured to the nearest 0.5 cm and 0.1 kg using a wall-mounted stadiometer and calibrated physician weight scale, respectively. Neck, chest, waist, and hip circumference measurements were obtained using standardized procedures24; the average of 3 measurements was retained.
Total body dual energy x-ray absorptiometry (DXA; Lunar Prodigy, GE Medical Systems, Madison, WI) measured body fat percentage (BF %), lean tissue mass (LTM), and fat mass (FM). Whole-body values were obtained as well as by region (i.e., arms, trunk, legs). A single technician conducted and analyzed all DXA scans. Quality assurance tests and phantom scans were performed prior to all measurement sessions. Because one participant exceeded the weight limit for the DXA, data from 42 participants were included for analysis.
Pulmonary function
Pulmonary function testing was conducted with a portable spirometer (Wizard, MicroMedical, Kent, UK) using standardized procedures.31 Maximal inspiratory and expiratory maneuvers were performed 3 times; averages of values obtained from the 3 inspiratory and expiratory flow-volume loops were used for analysis. Variables retained for analysis included forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1.0), peak inspiratory flow (PIF), and peak expiratory flow (PEF).
Respiratory muscle strength
Maximum static inspiratory (MIP) and expiratory (MEP) mouth pressures served as markers of respiratory muscle strength.32 MIP and MEP assessments were performed with respiratory pressure gauges (VacuMed, Ventura, CA) while seated with nasal clips. Assessments of MIP and MEP were obtained using standardized procedures,32 with the highest pressures developed over 3 consecutive efforts recorded. Respiratory muscle strength was calculated as (MIP+MEP)/2. Assessment of respiratory muscle strength was not possible due to equipment malfunction for one participant who subsequently discontinued the study. Data for the remaining 42 participants were utilized for analysis.
Research References
As always with these reviews, these are my takeaways from the article and I encourage you to read the article in its entirety. The references used in this article by the authors of this article are listed here.
Our Message
When you are looking for a Chiropractor near you that you can trust, choose one who will not only get rid of your back pain, neck pain, or headaches but who will also guide you to living a healthier lifestyle to keep you out of pain. Our East Dallas Chiropractors located in Lakewood, near the corner of Mockingbird Ln. and Abrams Rd., are here to teach you that taking care of your mental health and getting the proper nutrients are just as important as the chiropractic adjustment to stay healthy.
