Resilience for Older Workers With OA Through Exercise

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).

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.

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 40 Metre Walk Test. This test measures the time taken to complete a fast-paced 40 metre walk. The time taken to walk 40 metres is recorded in seconds. This measure has produced reliable and valid data in persons with knee OA.

Mobility performance will be measured using the Stair Ascent Test. For this test, the time taken to ascend 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 Stair Descent Test. For this test, the time taken to 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.

Mobility performance will be measured using the Timed Up and Go Test. This test measures the time taken to rise from a standard chair with arm rests, walk 3 metres, and return to a seated position. This measure has produced reliable and valid data in persons with knee OA.

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.

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.

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.

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/kg (grip force/body mass).

The peak torque developed during knee and hip extension and flexion during a maximum isometric contraction will be measured by use of a Biodex System 2 isokinetic dynamometer. Data will be presented as Nm/kg (torque/body mass).

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.