12 Secrets of Your Knee

The reason is usually not a lack of willpower. In a systematic review of treatment adherence in physiotherapy, the factors strongly linked with not keeping up exercise were: increased pain during exercise, low self-confidence, seeing many barriers, little social support, anxiety, depression and a sense of helplessness.

This programme was built for exactly these: a pain traffic light, small measurable steps, a promise card and someone close you can share your promise with.

X-rays and pain don’t always tell the same story. A review of studies found that only 15% to 76% of people with knee pain showed osteoarthritis on X-ray, and that 15% to 81% of people with osteoarthritis on X-ray had pain.

So even if your X-ray looks bad, your knee can get stronger and your pain can ease. The aim of exercise is not the picture on the film; it is your pain and your daily life.

On the front of your thigh: the quadriceps. Each time your knee bends and straightens as you walk, this muscle takes the load.

In a meta-analysis of 46,819 people, those with weak quadriceps were about 1.85 times more likely to develop symptomatic knee osteoarthritis if they were women, and 1.43 times if they were men. The quality of the evidence is low; even so, most of the exercises in this programme target this muscle.

Not always. According to the knee pain guide of an NHS musculoskeletal service, pain during or after exercise that stays below 5 out of 10 and settles within a day is acceptable, and you carry on exercising. Tired muscles are normal too.

If the pain goes above 5 or lasts more than 24 hours, review what you have been doing and ease off. The pain light at the end of each session works on this rule.

Almost nothing. In a study that followed habit formation in real life, it took 66 days on average for a new behaviour to become automatic, and missing a single opportunity did not significantly affect the process.

The problem is not missing once but missing often. When you miss a session, don’t blame yourself; go back to your next promise.

At the start you stood up times in 30 seconds; today, . That’s more stands. Your legs are getting stronger, and you measured it yourself.

At the start you stood up times in 30 seconds; today, again. Don’t worry: the result can vary from day to day and building strength takes time. The real comparison comes at the end of week six.

At the start you stood up times in 30 seconds; today, . Tiredness, pain or poor sleep can affect the result. Keep going with the programme; the real comparison comes at the end of week six.

Let today’s result be your new starting point. We’ll repeat the same measurement at the end of week six.

Here’s the secret: progress is hard to feel but easy to measure. Seeing your own number is one of the strongest reasons to keep going.

About four times as much. In a study of the walking of overweight older adults with knee osteoarthritis, each kilo lost was linked with a reduction of about four kilos in the load on the knee with every step.

Think of all the steps you take in a day: even a small weight loss gives your knee a big break. If you need to lose weight, talk to your doctor.

Because you make the decision only once. A meta-analysis of “if this happens, I will do that” plans found a medium-to-large effect on reaching goals, on average, across 94 separate tests.

The day, the time and the “after what” on your promise card are exactly this kind of plan. When the cue comes, you don’t have to think; you simply start.

The honest answer: noticeable, but not a miracle. In the latest Cochrane review of 139 studies and 12,468 people, exercise compared with no exercise improved pain by about 13 points and daily function by about 12.5 points out of 100 by the end of the programme.

The certainty of the evidence is low to moderate, and the effects were measured at the end of the programmes. That is why keeping it up matters as much as starting.

In an experiment, participants could listen to audiobooks they loved only at the gym. This group went to the gym 51% more often than the control group; the effect faded somewhat over time.

That is why the thing you chose to “listen to only while exercising” is on your promise card. Keep the rule: don’t listen to it at other times.

According to guidelines, morning stiffness in knee osteoarthritis is either absent or lasts less than 30 minutes. Over the age of 45, together with pain that gets worse with activity, the diagnosis can usually be made on examination.

If your stiffness lasts more than half an hour every morning, or your joints become swollen and warm, tell your doctor; there may be another cause.

For six weeks you have made time for your knee on the days you promised.

At the start you stood up times in 30 seconds; today, . That’s more stands.

At the start you stood up times in 30 seconds; today, again. Even if the number stayed the same, you kept your promise for six weeks, and that is a measurable gain too.

At the start you stood up times in 30 seconds; today, . If the result isn’t what you expected, review your programme together with a physiotherapist.

Note today’s number and measure again in a few weeks.

The real secret: the programme is over, and the habit is just beginning. Carry on twice a week. If you like, reset the map and unlock the secrets once more.