More swiss ball training! We're basically snowed in today so I couldn't get to the dojo. Most of my training tools were at the dojo except for a few things including my swiss ball. This exercise helps enforce putting your entire body mass into your techniques focused on single point.
If your arms are overly tense or a piece of your structure is off, the ball will shift around, fall, or you'll bounce off. The idea here isn't about how hard you can hit, but how heavy and relaxed you can hit to feel yourself "settle' into the techniques. Some hits will be good. Others not so good.
Its a fun and challenging exercise on a snow day.