Improving Resilience and Longevity for Workers Through Exercise

The purpose of this study is to examine the impact of an OA-specific aerobic and strengthening exercise program, delivered within the workplace, on mobility, pain, physical capacity, and resilience among workers with knee or hip OA as well as those with no joint pain. The investigators hypothesize that exercise designed for OA, delivered at work, will improve all of these outcomes.

The Canadian workforce is aging. The most prevalent age group is 50-54 years and most of these Canadians will aim to continue working over the next 10 years. However, the impact of arthritis on aging Canadians compromises their ability to continue working. By 2031, over 2 million Canadians aged 45 to 64 years will have arthritis. The investigators aim to boost the ability of adults with the most common arthritis, osteoarthritis (OA), as well as adults without OA, to engage in the workforce for as long as they desire. Identifying strategies to promote productivity among workers with knee and hip OA will be of great public health significance in the coming decades. However, the investigators face two challenges. First, obesity among sedentary workers is a risk for worsening knee and hip OA. Second, large occupational loads on the knee and hip worsen OA. Exercise has the most promise in addressing these challenges because it reduces pain and sick time, and improves mental health. Thus, there is a call for studies examining exercise for workers with knee and hip OA.

The participants in this arm will be asked to attend 3 group classes per week for 12 weeks taught by a certified exercise instructor. Five class times will be offered per week. These classes included a warm-up, static poses shown to decrease knee joint loading, and a cool down including flexibility exercises. Measurements will be obtained at baseline (before intervention) and at follow-up (following intervention). Outcomes included clinical mobility; pain; isometric leg strength; cardiovascular fitness; and resilience.

The participants in this arm will be asked to refrain from changing their physical activity over the 12 weeks and maintain any strategies typically used to manage knee and/or hip pain. Since it is known that exercise is beneficial for pain management and strengthening in knee OA, participants randomized to the no exercise group will be offered the same exercise program following completion of the study. Measurements will be obtained at baseline (before intervention) and at follow-up (following intervention). Outcomes included clinical mobility; pain; isometric leg strength; cardiovascular fitness; and resilience.

A biomechanical exercise program shown to decrease joint loading will be administered 3 times a week for 12 weeks. Outcomes included mobility performance; pain; strength; cardiovascular fitness; and resilience.

A no exercise (control) group will be asked to maintain their existing activity level for 12 weeks. Outcomes included mobility performance; pain; strength; cardiovascular fitness; and resilience.

The Lower Extremity Function Scale (LEFS) consists of 20 items, on an adjectival scale, that assess difficulty during mobility tasks ranging from transfers to running. Each item is scored from 0 (extreme difficulty or unable to perform activity), to 4 (no difficulty to perform activity). The minimum possible score is 0, and the maximum possible score is 80. Scores closer to 80 represent better self-reported physical function. It is reliable and valid in knee OA and has superior sensitivity to change compared to similar measures

Change in self-reported knee and hip pain will be assessed with 3 valid and reliable questionnaires: the Knee injury and Osteoarthritis Outcome Score (KOOS), the Hip disability and Osteoarthritis Outcome Score (HOOS), and the Intermittent and Constant Osteoarthritis Pain (ICOAP) score. The KOOS and HOOS pain scores represent a normalized score from 0 (extreme symptoms) to 100 (no symptoms). KOOS and HOOS scores closer to 100 indicate fewer symptoms. The ICOAP consists of two sub-scales: constant pain (5 items) and intermittent pain (6 items). The score from each subscale represents a normalized score from 0 (no pain) to 100 (extreme pain). ICOAP scores closer to 0 indicate less pain. The items from each subscale are averaged to produce a normalized ICOAP total score, ranging from 0 (no pain) to 100 (extreme pain).

The Disabilities of the Arm Shoulder and Hand is a 30-item questionnaire addressing upper extremity physical function and symptoms. The DASH is suitable for people with any upper limb musculoskeletal disorders and can also monitor changes in severity of symptoms and functional abilities over time. Each item is scored from 1 (no difficulty) to 5 (unable). Total scores range from 0 to 100, with higher scores indicating more upper limb problems.

The peak torque developed during knee extension and flexion during a maximum isometric contraction will be measured by use of a ergoFET hand-held dynamometer.

Grip strength will be assessed using a Jamar hand dynamometer. The hand dynamometer will be set to a fixed position and all values of grip force will be expressed in kg.

Cardiovascular fitness will be calculated using the Single Stage Treadmill Walking Test. Predictions of VO2max will be made from heart rate (measured with a heart rate monitor), walking speed, age and gender.

Mobility performance will be measured using the Six-Minute Walk Test (6MWT). For this test, participants are instructed to walk as far as possible in 6 minutes. The distance covered in 6 minutes is recorded in metres. This measure has produced reliable and valid data in persons with knee OA.

Mobility performance will be measured using the Stair Ascent and Descent Test. For this test, the time taken to ascend, as well as descend nine stairs is recorded in seconds. This measure has produced reliable and valid data in persons with knee OA.

Mobility performance will be measured using the 30-second Chair Stand Test. This test measures the number of times participants can rise and lower from a standard height chair, without using arm rests, in a 30-second period.This measure has produced reliable and valid data in persons with knee OA.

Resilience will be measured using the Resilience Scale 25 Survey, which is a 25-item questionnaire designed to evaluate a participants ability to adapt to stress and adversity. The test is scored out of 175 (scores ranging from 25 to 175), with higher scores indicating higher resilience.

The Work Ability Index (WAI) is a widely-used self-report questionnaire that evaluates a worker's capacity to perform a job accounting for their physical and mental well-being in addition to the demands of their job. The WAI consists of seven dimensions including current work ability relative to life-time best, work ability related to job demands, number of current physician-diagnosed health conditions, estimated work impairment due to the conditions, sick leave over the past year, own prognosis, and mental resources. Total scores range from 7 to 49 and can fall under one of four classifications: poor work ability that should be restored (7-27), moderate work ability that should be improved (28-36), good work ability that should be supported (37-43), and excellent work ability that should be maintained (44-49). The WAI produces reliable data.

Depression will be assessed with the Centre of Epidemiological Studies Depression (CES-D) Scale, a 20-item scale developed for the general population with emphasis on affect. Elements of affect include mood, guilt, worthlessness, helplessness, appetite, and sleep. Each item is scored from 0 (rarely or none of the time), to 3 (most of the time). The items are summed to produce a total score between 0 and 60 with a score of 16 or higher indicating depression.

The Arthritis Self-Efficacy Scale (ASES) measures arthritis-specific beliefs regarding perception of performance on certain tasks to cope with the disease. The ASES is measured using 20 questions on a 10-100 scale with respect to three main areas: pain management (5 questions), physical function (9 questions), and other symptoms (6 questions). Each question is scored from 10 (very uncertain), to 100 (very certain), in 10-point increments. The minimum score for each subscale is 10, and the maximum score for each subscale is 100. The scores from each subscale are averaged to produce a normalized total score. Scores closer to 100 indicate greater certainty that a participant can cope with a particular task as a consequence of their disease.

Inclusion Criteria: full-time or part-time administrative employees Exclusion Criteria: Any other forms of arthritis Osteoporosis-related fracture History of patellofemoral symptoms Active non-arthritic hip or knee disease Hip or knee surgery Use of cane or walking aid Unstable heart condition Neurological conditions Hip, knee or ankle injuries in past 3 months Physician-advised restriction to physical activity Any injuries that would prohibit participation in exercise Ipsilateral ankle conditions Currently receiving cancer treatment Currently pregnant

Mulla DM, Wiebenga EG, Chopp-Hurley JN, Kaip L, Jarvis RS, Stephens A, Keir PJ, Maly MR. The Effects of Lower Extremity Strengthening Delivered in the Workplace on Physical Function and Work-Related Outcomes Among Desk-Based Workers: A Randomized Controlled Trial. J Occup Environ Med. 2018 Nov;60(11):1005-1014. doi: 10.1097/JOM.0000000000001408.