Walking uphill makes us sweat - some scientists agree

I have been reading some older papers on mechanics of walking:

Cavagna GA, Margaria R. 1966. Mechanics of walking. J Appl Physiol 21: 271–278.

Cavagna GA, Saibene FP, Margaria R. 1963. External work in walking. J Appl Physiol 18:1–9.

One interesting piece of evidence that I came across was the following: Margaria (MARGARIA, R. Atti reale accad. naf. Lincei, Ser. VI. 7 : 5, 1938.) has shown that, in uphill walking (positive work), the efficiency, as expressed by the ratio of body lift to energy expenditure, tends to a maximum value of 0.25, while in downhill (negative work) walking or running it tends to 1.20.

I take this to mean that if I use 100J of chemical energy to walk uphill I could hope to gain as much as 25J of gravitation energy and generate 75J of thermal energy. On the other hand if I use 100J of chemical energy to walk downhill I would lose 120J of gravitational energy and generate 220J of thermal energy. In order to gain 100J of gravitational energy I would have to use at least 400J of chemical energy and generate 300J of thermal energy. So for the same change in height more thermal energy is generated on the way up, 300 vs. 220.