Functional exercise and performance system

The system tests functional capacity — strength through range, movement speed, endurance and movement quality — and compares results against normative values and against the patient's own earlier results. Output is a set of numbers rather than a therapist's rating.

It then drives the exercise programme from those numbers, with load and progression set on measured capacity rather than on estimate.

Return-to-work and return-to-sport decisions, where a defensible number is needed rather than an opinion. Post-surgical progression, particularly after ACL reconstruction where limb symmetry index governs clearance. Sarcopenia and geriatric strength programmes. Occupational capacity assessment.

Also for the mid-programme review, where the question is whether the current plan is working.

Progression decisions made on how a patient feels are wrong often enough to matter, in both directions: some patients feel ready months before their strength symmetry supports it, and others remain cautious long after the numbers say they can progress.

Testing also makes failure visible. If eight weeks of work produced no measurable change, that is information we act on rather than continue past.

Force and power measured objectively, which matters because self-assessed strength and observed effort are both unreliable — particularly in the presence of pain, which inhibits muscle independently of weakness.

Symmetry between sides is the figure that matters most after single-limb injury, and it is the criterion used for return to sport rather than elapsed time.

After an injury affecting one side, absolute strength says little — a strong person with a weak leg still looks strong. The comparison against the other side is what identifies the deficit.

A commonly used threshold before returning to sport is around ninety per cent symmetry, and athletes who return below it re-injure more often 1. This is why testing replaces the calendar in return-to-sport decisions.

Yes. Symmetry compares the injured leg with the other leg, and the other leg can also lose strength during the months of reduced activity after an injury, which makes the ratio look better than the knee really is 2. In a cohort of 70 athletes tested six months after ACL reconstruction, 40 reached 90% symmetry on quadriceps strength and hop tests, but only 16 of those 40 had also regained 90% of what the uninjured leg could do before surgery 2.

That pre-surgery comparison also picked out more of the athletes who later had a second ACL injury, although the study was small and its authors call the finding preliminary 2. It is one reason to test both legs at the start of rehabilitation and not only at the end: an early baseline is a truer reference than the other leg alone 2.