1. The problem statement, all variables and given/known data A 65 kg man goes for a 72 minute hike up a mountain that is 400.0 metres in vertical height. The energy consumption rate for this climb is 10.1 kcal/min. What is the Mechanical Energy (useful work energy) expended for this hike? (in kcal) 2. Relevant equations ME= (Efficiency x Eout)/100 3. The attempt at a solution 10.1 x 72 = 727.2 (Therefore Eout=727.2) But I don't know the efficiency! So how do I figure this out?