When I workout at the gym I usually do the same routine. My muscles are used to it so I don’t feel sore afterward unless I alter the pattern. When I lift weights slowly and with concentration, or if I switch things up a bit and try yoga or Pilates, my muscles are noticeably sore the next day.
In handbell rehearsals, sometimes I ask the musicians to ring sections of the piece slowly. I also do this when practicing piano and organ. This helps to solidify the correct notes and challenges me to think in a different way.
During Lent, I plan to exercise my spiritual muscles in various ways. Although physical exercise can bring soreness, it also produces strength. Although I may not see results from practicing these spiritual disciplines, I know God is strengthening me through them.