Hi Finley, start with a run walk plan that keeps you moving for 30 minutes without overloading the knee. Example for the first two weeks: 5 minute brisk walk warm up, then 1 minute easy jog and 2 minutes walk repeated 7 times, then a 4 minute cool down. Each week add 30 seconds to the run and trim 30 seconds from the walk while keeping the 30 minute total, and only progress if next day soreness is mild. Use this pain rule to guide you: up to 2 or 3 out of 10 during the run that settles within 24 hours is acceptable and but if it spikes above that or lingers past a day, step back one week. Run three nonconsecutive days and keep the jog truly easy with a pace where you could talk in full sentences.
Do a quick strength set right after runs or on off days to calm the knee and build capacity. Two sets of 8 to 12 slow split squats, step downs from a 6 inch step, banded side steps, and calf raises is plenty for the first month. Keep strides short and increase cadence slightly by about 5 to 10 percent, choose flat routes, and avoid long downhills or cambered roads while things settle. Make sure shoes are not beat up and have some cushioning, and swap one run for 30 minutes of easy cycling or brisk walking if the knee needs a lighter day. If you see swelling, locking, or pain that wakes you at night, get it checked rather than pushing through.
