By resources I wasn't necessarily referring to calories consumed. I was thinking of something like stem cells or some other resource useful for repairing damaged tissues that might be deliberately restricted or "turned off" by the body as part of the process of shutting down overall growth.
The rate of aging seems to be tied to the rate of growth with slower growing organisms also aging more slowly so you might expect GH-deficient mice to live longer if it resulted in a slower rate of growth.
Hopefully turning growth back on for a short period of time would not result in the body actually growing larger in size. With luck, resources made available by new growth would go to repair tissues damaged by aging before initiating new growth.