Table 3 Summary of walking program

30 min duration, 5–7 days/week at a moderate intensity (moderately out of breath, moderately difficult to talk)

WEEK 1

Find baseline walking tolerance (3–4 walks to tolerance)

Each participant’s unique walking tolerance is determined by having the participant take 3–4 walks during the following week (number of walks individualised to the participant by therapist), and recording how far (time/distance) they can walk before they experience a significant increase in knee symptoms (operationalised as a significant increase in their knee pain [≥2 points on an 11-point NRS) or knee swelling [visually noticeable) or pain/swelling that lasts [~ 2 h] after they finish walking.

In Week 1–4 (weekly in-person sessions), the therapist guides the walking program and assists the participant in planning the dates and times that the walks will be undertaken.

WEEK 2

“Start” walking level (80% of baseline tolerance, 4–5 walks)

Goal setting

The therapist takes an average of the walking time/distance over the 3–4 baseline walks, with 80% of this time/distance used as the “start” walking level for the following week, but with an additional day of walking (e.g., if 3 walks performed in Week 1, Week 2 involves 4 walks at 80% of Week 1’s time/distance).

Facilitated, individualised goal-setting: the therapist assists the participant in creating short- and long-term activity-related goals (using Specific, Measurable, Achievable, Relevant, Time bound [SMART] format). These goals are used to help individualise the subsequent walking program.

WEEK 3

Progress 10% (90% of baseline walking tolerance, 4–5 walks)

The participant progresses to 90% duration of their baseline walking tolerance, keeping the total number of walks constant (i.e., 4–5 walks).

WEEK 4

Progress 10% (100% of baseline walking tolerance, 4–5 walks)

Goal review

The participant progresses to 100% duration of their baseline walking tolerance, keeping the total number of walks constant (i.e., 4–5 walks).

Short- and long-term goals are reviewed.

WEEK 5–8

Progress 10% or increase number of walking days

Goal review (Week 8)

Weekly progressions either by increasing the walking duration by 10%/week or by adding in additional walking days, but not both. The choice to add duration or walking days is individualised to the participant and guided by the minimum activity goal of the trial.

In Week 5–8 (weekly telehealth sessions), the physiotherapist assists the participant in updating the walking program, with the aim of having participants able to independently progress their own program.

At Week 8 (telehealth session), the therapist assists the participant in planning activity for the subsequent weeks until the Week 12 session, and the short- and long-term goals are reviewed.

WEEK 9–12

Progress 10% or number of days or additional progression strategies (see below)

Goal review (Week 12)

After the minimum activity goal of the trial is met in terms of duration and walking days, intensity is increased by increasing walking speed (if applicable). Individualised progression can also occur in terms of types of walks, progression to jogging.

If a flare-up is experienced (at any time), the therapist assists the participant in appropriately revising the walking program.

At Week 12 (telehealth session), the therapist assists the participant in planning activity for the subsequent weeks (in-person session at Week 21) and the short- and long-term goals are reviewed.

Week 13–52

Progression strategies or maintenance

Goal review (Week 21, 39)

Individualised progression strategies are undertaken. If participant has met the minimum activity goal and does not want to further increase activity, maintenance planning is undertaken.

At Week 21 and 39 (5 and 9 month in-person follow-up physiotherapy sessions), the therapist assists the participant in planning activity for the subsequent weeks and the short- and long-term goals are reviewed.

ADDITIONAL PROGRESSION STRATEGIES

To individualise progression to the individual and their personal activity goals.

Walking intensity: Walking speed is increased, using breath and ease of talking as a guide for intensity (low intensity: minimally out of breath and easy to talk; moderate intensity: moderately out of breath, moderately difficult to talk; vigorous intensity: out of breath, difficult or unable to talk).

Initiation of new walking activities (e.g., hiking up hills, walking on different terrain): Baseline tolerance is first evaluated using 3–4 walks over a week, followed by initiation of 4–5 walks the following week at 80% of tolerance. Alternatively, different types of walks (hills, differing terrain) may also be integrated within normal walks (3 normal walks, two hill walks/week).

Jogging: Baseline tolerance is evaluated by interspersing 1 min jogging with 1 min walking intervals. Relative jogging time is progressively increased over weeks (e.g., week 2: 2 min jogging, 1 min walking; week 3: 3 min jogging, 1 min walking), keeping the total duration constant. Once the participant can jog for the entire baseline duration, then jogging time/distance/intensity can be increased.