Get Comfortable Being Uncomfortable

This is more of my rambling thoughts regarding personal preparedness during my morning commute. I'm not a masochist, just someone who likes to do as much as possible to become more prepared for whatever discomforts I may face. Remember to be safe, but use this idea to become more mentally - and possibly physically - prepared to cope with discomfort during emergencies/disasters.

Note that there are many other possibilities for discomfort that I didn't mention. Some others include:
Carry a moderately heavy pack whenever you go for a walk. It's not only good exercise, it also builds capacity to carry weight for extended distances without undue discomfort when necessary.
Occasionally experiment with sleep deprivation for short periods. Adequate sleep is healthy and beneficial, but it can be useful for preparedness to practice concentration and complex tasks while extremely tired.
Stand (or sink into a deep squat) more often rather than immediately looking for a place to sit down. Aside from it being healthier, you never know when you could be in a situation where there is nothing available for comfortable seating.
When working out, occasionally do ultra-high rep sets. They have great physical benefits as well as requiring mental toughness. High-rep squats leave me sore for several days. The simple act of starting a set knowing the inevitable pain ahead requires one to mentally accept and commit to facing that challenge.

I could go on, but won't. Feel free to list additional ideas for deliberate discomfort, or discuss your thoughts on what I presented.