Effects of Core Stabilization Exercises on Pulmonary Functions, Respiratory Muscle Strength and Functional Capacity

In recent years adolescent substance abuse is a serious and growing problem. Substance use among adolescents means the use of alcohol, opiates, amphetamines, inhalants, cocaine, marijuana, benzodiazepines, hallucinogens, and anabolic steroids. The United Nations Office on Drugs and Crime reports that approximately 5% of the world's population used an illicit drug in 2010 and it is estimated that heroin, cocaine and other drugs are responsible for 0.1 to 0.2 million deaths per year.

There is a limited number of studies in the literature that investigate the relationship between substance use disorder and respiratory functions. In Taylor et al., study reported that the proportion of cannabis-dependent study members with an FEV1/FVC ratio of, 80% was 36% compared to 20% for non-smokers. Another research of Taylor et al., in longitudinal observations over 8 years in young adults (cannabis smoking on lung function in young adults between the ages of 18 and 26) revealed a dose-dependent relationship between cumulative cannabis consumption and decline in FEV1/VC. In a monograph, stated that follow-up studies of regular cannabis-only smokers also found impaired respiratory function and pathological changes in lung tissue like those preceding the development of chronic obstructive pulmonary disease .

The core anatomically described as a box, with the abdominals at the front, spinal and gluteal muscles at the back, the diaphragm on the top, and the pelvic floor and hip muscles on the bottom. Correct breathing is vital to abdominal training because respiratory muscles are directly involved during common core stability exercises. Moreover, the diaphragm, a component of core stability, plays a role in respiration and trunk stability by controlling intra-abdominal pressure . Oh et al.reported that, 30-min, 3 days a week for 8 weeks lumbar stabilization exercise had a more positive effect on pulmonary function than general physical therapy on stroke patients.

Our hypothesis was that core exercises may positive effect on respiratory functions and functional capacity of substance use disorder individuals. The aim of our study is to investigate the effects of core exercises on respiratory functions and functional capacity in adolescents with substance use disorder.

Subjects: The study sample comprised of 15-18 year old male. Participants were required to be in-residence at the treatment center and meet Diagnostic and Statistical Manual-V criteria for substance use disorder in Mental Health and Neurological Diseases Training and Research Hospital for Psychiatry, Neurology and Neurosurgery; Child and Adolescent Drug and Alcohol Dependence Treatment Center (CEMATEM) in Istanbul.

Sample Size Determination: The sample size and power calculations were performed using the Instat sample size calculator. The calculations were based on the average value of the 6-Minute Walk Test in the 15-20 age group was 725.8 meters and the standard deviation (SD) was 61.2 meters (28), in the 95% confidence interval, an alpha level of 0.05, a β level of 5% and a power of 95%.These parameters generated a sample size of at least 18 participants for each group.

Randomization Study Protocol: The participants were randomly assigned to 1 of 2 parallel groups to receive either Exercise or Control. To allocate the participants to the groups, using the method of randomly permuted blocks using Research Randomizer, a program published on a publicly accessible official website (www.randomizer.org). Computerized random numbers were conducted, and sequentially numbered index cards with the random assignment were prepared. The index cards were folded and placed in sealed, opaque envelopes. Then, the investigator opened each envelope and allocated the participants to the Exercise or control group according to the selected index card.

Eligibility Criteria:
Inclusion Criteria:

* were between 15 and 18 years of age,
* met current Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) criteria for substance use disorder,
* be using substances over a year,
* have not participated regularly in any exercise training program for the past six months,
* were currently engaged in inpatient substance abuse treatment.

Exclusion Criteria:

* a history of psychotic disorder or current psychotic symptoms,
* physical disabilities or medical problems,
* inability to adapt to the evaluation and treatment program,
* have a respiratory system problems such as bronchiectasis, asthma and tuberculosis, infectious health problem (HIV, hepatitis B etc.).