You’re halfway through your physical therapy exercises and your knee starts hurting. Do you push through? Stop immediately?

This question keeps more people from recovering than almost anything else. The fear of making things worse can be paralysing – but so can being too cautious. Let’s clear this up once and for all.

The Golden Rule

• Good pain: Discomfort during exercise that fades within a few hours and doesn’t increase the next day.
• Bad pain: Sharp, stabbing, or burning pain that gets worse as you continue, lingers for hours afterward, or makes your knee swell significantly.

Understanding Good Pain (Healing)

• What it feels like:
  • A dull ache or burning sensation in your muscles
  • Stretching or pulling sensations
  • General soreness like you’ve worked hard
  • A score of 3-5 out of 10 on a pain scale)
  • Discomfort that improves with movement or warm-up
    
• Why it’s actually good: This is your body adapting and getting stronger. Joints need controlled movement to produce lubricating fluid. Think of it like starting a rusty hinge – there’s friction at first, then it moves more smoothly.
  
• What to do: Continue the exercise but monitor closely. If the pain stays at the same level or decreases as you continue, you’re okay.

Recognising Bad Pain (Warning Signals)

• What it feels like:
  • Sharp, stabbing, or “electric” sensations
  • Clicking, popping, or grinding accompanied by pain
  • Pain that gets progressively worse with each repetition
  • A score of 7-10 out of 10 on a pain scale
  • Pain that shoots down your leg or up your thigh
    
• Why it’s bad: This is your body saying “stop – you’re causing damage.” This could be inflammation flaring up or a structure being stressed beyond its capacity.
  
• What to do: Stop the exercise immediately. Try a modified version with less range of motion. If pain persists, skip that exercise.
  
  

The 24-Hour Test

Here’s a reliable way to know if you overdid it:

• Pass: Your knee feels about the same or slightly sore the next day, similar to how your muscles feel after a good workout.
• Fail: Your knee is significantly more painful, swollen, or stiff than before you exercised. If you fail the 24-hour test, scale back by 50% next time.
  
  

Specific scenarios: Push through or stop?

1. Wall sits make your thighs burn intensely: Push through. That’s muscle fatigue, which builds strength.
2. Straight leg raises cause a sharp pain behind your kneecap: Stop. Sharp pain in the joint is bad pain.
3. Your knee aches during heel slides but improves by the 5th rep: Push through. Pain that decreases with movement is typically stiffness working itself out.
4. Step-ups cause clicking and sharp pain with each step: Stop. Painful clicking suggests something catching.
5. Squats make your knee feel unstable: Stop. Instability is a warning sign.
   
   

The bottom line

Healing requires challenging your knee within safe limits. Too cautious and you’ll stay weak. Too aggressive and you’ll trigger setbacks. The sweet spot is working at a 3-5/10 discomfort level that doesn’t create lasting pain or swelling.