This is a great proprioceptively enriched exercise that improves limb awareness, long term joint stability and injury prevention, limb adductor muscles – dynamic stretch.
Lure your dog to step sideways via correct reward placement, with immediate praise + follow on reward when their paw reaches the desired target. Once the association has been formed, your dog will actively seek the target and the distance can be established.
Only ever work under the direct instructions from your therapist e.g. set up, distance, repetitions and frequency. Check for signs of fatigue and be prepared to cut sessions shorter if desired.