Muscle atrophy in kl/kl mice was caused by growth hormone depletion and poor muscle regeneration (Balkovic and Hsiung, 1985; Rubinek and Modan-Moses, 2016; Sahu et al., 2018), but we considered that exacerbation of muscle atrophy involved disuse muscle atrophy (Kuro-o et al., 1997; Wall et al., 2013; Eren et al., 2014). This evidence concerns the gene GH1 and Atrophy.