Walking up and down stairs

The above calorie count is based on a weight of 188 pounds (85.35kg) and a flight of stairs being 4.47m high.  The formula is E = mgh / 1000 where E = energy in calories, m is the mass (your weight) in kg, g is gravity (9.81 m/s²), h is the height of the flight of stairs in meters.  In this case, E = (85.35) x (9.81) x (4.47) / 1000 = 3.74 calories per flight of stairs going up and about 1.40 calories burned going down (about 37½% of going up calories). 
It takes an average of 18 seconds to ascend one flight of stairs and about 10 seconds to descend one flight.  In order to compute the time for one hour of exercise, we need the formula 10f + 18f = 3600, which translates to 28f = 3600, and f = 128.57 flights of stairs in one hour round trip.  If I do, 128.57 flights of stairs up and 128.57 flights down, with going downstairs taking about 37.5% of the needed calories, this would produce this equation:

E = (3.74 cal/flt x 128.57 flts) + (1.40 cal/flt x 128.57 flts), so E = 661.65 calories per hour.