Do Obese Patients With Primary Knee Osteoarthritis Benefit From a Single Bout of Moderate Intensity Aerobic Exercise?

Study population:

This is an observational study a cohort of sedentary Egyptian patients included thirty four obese patients role diagnosed with primary human knee joint OA according to the criteria of the American College of Rheumatology (ACR)( 8).were selected from those attending the outpatient clinics of Rheumatology and Rehabilitation Department , Mansoura University (28 females and 6 males; mean age, 46.94 ± 10.84 years; trunk mass index, 40.91 ± 10.09 kg/m2). In addition, 30 healthy volunteers with no clinical and radiological evidence of OA(22 females and8 males; mean age,50.7 ±10.5 ; BMI 24.3±1.3)participated in the discipline .

Inclusion criteria: knee OA with obesity; sedentary with no previous education ; ability to understand and follow commands; and ability to walk independently.

Exclusion criteria: Medical conditions contraindicating moderate aerobic exercising (as determined through prescreening questions, i.e., cardiac or coronary artery disease as ischemic cardiomyopathy , chronic lung disease, asthma, uncontrolled hypertension), inability to exercise via treadmill(i.e. no neuromuscular or lower extremity conditions or any other medical contraindication that could prevent them from floor walking as upset affecting movement of the pelvic arch or pace , story of previous hip or knee operating room ,periarticular fractures, or lower limb injuries).History of recent reefer transmission or acute joint lighting .History of recent joint injection (steroid, hyaluronic acid , etc.) within 6 calendar week of study. Ingestion of antioxidant supplementation and the use of psychotropic agents.

Participants underwent bilateral AP standing x ray to verify the presence and degree of human knee OA. X-rays were marked exploitation the Kellgren and Lawrence (K/L) scale for knee OA severity(9).Subjects with picture taking knee OA of KL grade ≥2 in a minimum of one knee were listed. The grading of the worst affected knee in every patient was used for knowledge analysis.

Physical examinations including age and body mass index (BMI) were obtained at the same visits at which radiographs were obtained. Western Ontario and McMaster Universities Arthritis Index (WOMAC) scores of the OA patients were collected (10).

Treadmill Training Protocol

Each eligible participant in the patients group was then prospectively assigned to undergo exercise session of full-body-free weight treadmill training. Once the participants were prepped, they performed stretching for 5 min and slow walking for 3 min as a warm-up exercise before starting the training. Stretch was carried out similarly to all the subjects to quadriceps femoris and the hamstring. In the warm-up time period , it was enforced for 3 min at the speed of1 km/h. Then patients began the walking trials and walked at 1 to 1.34 m/s on an electric car treadmill (JACO fitness: JACO-212C).

Exercise intensity

For the purpose of this study, Metabolic Equivalents (METs) and Rate of Perceived Exertion (RPE) were used as guidelines to determine exercise intensity. Moderate aerobic exercise has been objectively defined as activity that generates energy expenditure of 3.0 to 6.0 (METs) (11).

To determine the intensity, time and frequency of exercise, it was set at low to moderate, that is between 40% and 60% of the maximum heart rate, from 12 to 14 rating of RPE. In addition, each subject was shown the 15 point Borg Rating of Perceived Exertion scale and instructed in its use. The RPE scale was mounted on the wall in front of the treadmill and easily visible to the subjects. Exercise instructions and measurements of associated Metabolic Equivalents (METs) were determined based upon previous studies which determined that walking on a level surface at 3.0 MPH equates to 3.3 METs and walking at 4.5 MPH generates 6.3 METs(12).

Participants walked at a pace of 2.5 to 3.0 MPH on a treadmill with zero incline for 30 min and they were instructed to walk at a pace that neither caused pain nor increased symptoms (13).

To minimize pain that may occur due to treadmill exercise, 5 min rest were allowed after 15 min of exercise. In the control group, the subjects remained at rest.

The present study was conducted in agreement with the guidelines of the Declaration of Helsinki. Written informed consent was received from every patient and healthy subject before participating in the study. This study was approved by the Institutional Research Board of the Faculty of Medicine, Mansoura University code R.18.04.137

Laboratory assays:

Blood samples were drawn before and once exercise (within 0.5 h once exercise,and at 24 h). All organic chemistry measurements were performed on frozen plasma samples obtained by activity of freshly drawn blood (3000 × g for 20minutes at 4∘C) and consequent storage at -70∘C. Blood macromolecule profiles, together with total cholesterol (TC), HDL cholesterol (HDL-C), calculated LDL cholesterol(LDL-C), and triglycerides (TG) concentrations were determined by protein assays., further as abstinence blood sugar level.

IL-6, CRP Serum concentrations of IL-6 were determined using sandwich high sensitivity ELISA kit for quantitative detection of human IL-6 according to manufacturer's protocol (Boster Immunoleader by Boster Biological Technology Co. Inc.). Detection of serum CRP was performed by Solid Phase Sandwich ELISA according to manufacturer's instructions (Quantikine Human CRP Immunoassay, R&D systems)

Glutathione reductase assay:

Spectrophotometric determination of GR activity in the serum was measured as described by Calberg and Mannervic (14) using commercially available Glutathione Reductase Assay Kit(Sigma chemical company, St Louis, Missouri, USA). Glutathione reductase catalyzes the reduction of GSSG by oxidizing NADPH to NADP+. The decrease in absorbance was measured at 340.