If there’s one thing I’ve got experience with, it’s injuries. As always, I don’t claim to be an expert here, but with a broken clavicle, broken femur, sublexed patella, subluxed wrist bones, bursitis, and a psoas that can best be described as “too tight,” I definitely have some experience with training under less than optimal bodily conditions.
First off, let me clarify that most of these conditions are not the result of aikido training. The broken collar bone was, (the result of me taking a fall incorrectly and getting caught in my partner’s hakama), as are the wrists (results of overly-aggressive kotekaeshi), but the rest came along outside of regular aikido practice. Regardless, they have affected my training, namely by interfering with it, on occasion, or causing me to be aware of it and having to compensate on the mat.
With any condition that can affect your training, you must ask yourself if it is better to take a break, or to resume training and be (more) cautious (than usual). In my early 20’s, it was simple – unless I was in a lot of pain, I’d push myself and not let an injury keep me from practice. Now that I’m in my late 30’s, I think that was pretty dumb. Yes, on the battlefield or in a fight for your life, the ability to push beyond pain is not only admirable, it’s probably required to survive. But the fact is that in today’s training, that’s not the circumstance I face on a regular basis, and therefore resting and letting injuries, even minor injuries, heal is the better course of action.
That having been said, I am usually in some sort of pain on any given day, whether it’s my knee, my hip, my shoulder, or something else. While I do take measures like stretching, massage therapy, chiropractic, etc., to head it off, there is usually something that’s “not quite right.” However, unless they’re especially bad, I don’t let pains interfere with aikido any more than they do with the rest of my daily life. In other words, if my knee isn’t hurting badly enough to keep me from going downstairs for a cup of coffee, it’s not keeping me off the mat either.
The key is being honest with yourself when deciding whether an injury or sickness should keep you from training. Do you really feel bad enough that practice will be more difficult, or are you just making an excuse to skip class? Do you feel “pretty good,” despite that twinge in your lower back? Is it likely to get worse with training, or better? If you honestly think that it won’t get better, taking some time to rest and heal is probably the better option.