Research subject is about to turn 50 and curious about stacking with Tirzepitide

Subject line pretty much sums it up. Research subject as being on TIRZ for managing weight and blood sugar for over a year. Now with weight stable, they find that some of the weight loss has been at a cost of lean muscle mass. While continuing maintenance of 7.5 MG of TIRZ/week I’m curious about adding a Sermorelin protocol. Research subject, trains, five days a week mostly functional strength with endurance cardio. Any insights would be appreciated.