Riding for strength pedalling at 50 t chainring all through out at RB, and 42 at MTB

Wheels of Happiness

Rizal Philippines

4.16.2021.

Yesterday, I rode up to Morong using only 50t chainring.  Its same chainring on flats and hills.  For the hills it was 50 x  30     Today at quarry road, I road up hill using 42 x 32.   My legs and thights now ache.

At the steepest part, I downshifted to 32.    (No choice, otherwise the bike stops moving and fall)

I understand that is the rationale for the one by.   To use only one chain ring through out the shifting range.  

What do you choose at number of teeth for the crank:  30, 32, 32, 34, 36, or 38.?

I would choose 34.   That would be the ideal gear for a RB and MTB especially for senior. 

Converting to a one by MTB 

One by 9 speed is better?