Burrow and those around him are hopeful that the longer he goes without any setbacks, the more he will be able to continue his recovery and move closer to full strength. One of the challenges with this type of injury is that despite the existence of metrics that can show progress in various areas (e.g. strength/power/endurance/acceleration), there is no single definitive test or measurement that can ensure there is no risk of recurrence with activity.

Perhaps equally important to restoring preinjury performance, yet more difficult to measure, is confidence. Return from a calf strain, particularly after a setback, can impact an athlete’s confidence that the muscle will respond as it should on demand, without failing.

“The hope is that he’s getting better every time he steps out there and feels more confident as he plays,” said Bengals offensive coordinator Brian Callahan. “I think that that’s where his mindset is too. He feels better and plays better and starts to get a little momentum back from dealing with it for as long as we have.”