Funny how a lot of our skills and faculties need exercise. If I don't drive my husband's car (manual transmission) once in awhile, I become more uncomfortable with the idea of driving it and more awkward in changing gears when I finally try. Last year, when I started riding a bicycle again after not having ridden one in over ten years, it took a little while to get my body used to that kind of exercise. When I work with my middle-schooler on Math, it sometimes takes a little adjustment to get "up to speed"; but when I start to do this more often, my comfort level and ability to solve problems is much better. Our bodies need exercise, our minds need exercise, our wills need exercise. Exercise makes us stronger, frequent exercise builds habits and makes hard work come easier and more naturally. When we keep our bodies, minds and wills in good shape, it keeps us happier and healthier in each of those realms.
One of the reasons I like homeschooling is that it forces me to exercise my brain more than I would have otherwise. One of the reasons I am so fortunate to have children is that they have made me a better person than I was before (not that I don't still have a long ways to go, :)