[Andy Reed]

Good question.  If you are truly overtrained (and I say this because it is worth a medical check up to evaluate for other causes) then I would not recommend significant strength training until you have rebuild your aerobic base. Whilst most of the published work on Overtraining Syndrome (OTS) has been done in the endurance realm, there is some evidence that pure strength based athletes, such as power lifters, can become overtrained, though it does seem to be much less common. Heavy lifting adds significant load and stress to the system, so it definitely makes sense to limit this as you recover, at least until you “rebuild the aerobic house”. I think the best approach for you and your goals, if you are feeling better after a period of rest, is to get back to some easy aerobic paced activity, probably just short flat walks initially, and build from there. Use nasal breathing to guide intensity, or perform a walking Aerobic Threshold test on the flat to get some idea of your target HR. Unfortunately it takes time to rebuild this base, but with patience you will get there. I think that some mobility and light core work is quite acceptable however, as the overall global load for this type of activity is low.