DDIT3 and obesity due to melanocortin 4 receptor deficiency: Eight weeks of high-intensity ladder climbing (80%–100% body weight added in 25o inclination, 3 sessions/week) was shown to decrease the levels of ER stress-related proteins, such as the phosphor-PERK (p-PERK)/PERK ratio and the C/EBP homologous protein (CHOP), a downstream of PERK that led to myocardium injury in male rats (50 weeks old) with obesity (Kim et al., 2017; Kim et al., 2018).