Resting metabolic rate and blood lipid changes of an experienced backpacker hiking the Appalachian Trail

ObjectiveTo evaluate the effects of a long-distance backpacking trip on resting metabolic rate, body composition, weight, and blood lipid profile. MethodsSingle-subject (male, aged 61 years) study of an experienced backpacker who hiked 151 days on the Appalachian Trail. Resting metabolic rate (RMR) was measured pre- and post-hike, body composition was assessed pre-, mid-, and post-hike and blood lipids were measured pre-, early-, mid-, and post-hike. ResultsPre-post differences showed decreases in body fat (-12.2% [-39%]) and body weight (-21.32 kg [-23%]). Changes associated with RMR showed decline in RMR 24 hours (kcal; -124 [-7%]), increase in both RMR 24 hours kcal/total mass (+3.79 [+21%]) and RMR 24 hours kcal/lean mass (+0.75 [+3%]), and change in respiratory exchange ratio (RER) from 0.92 to 0.83. Pre-post differences in blood lipids were as follows: triglycerides (TG; -499 mg/dL [-84%]); total cholesterol (TC; -131 mg/dL [-43%]); high-density lipoprotein cholesterol (HDL-C; +17 mg/dL [+44%]); low-density lipoprotein cholesterol (LDL-C; -46 mg/dL [-33%]); LDL-C/HDL-C ratio (-1.92 [-53%]); and TC/HDL-C ratio (-4.69 [-61%]). ConclusionThe physical activity associated with an extended backpacking adventure can very positively impact resting metabolic rate, body composition, weight, blood lipids, and lipoproteins.