At 55, I don’t bounce anymore, but I also try not to cry.

When a judo player younger than all four of my children grabs my arm and throws me with it or sweeps my foot so I fall on my back or trips me sideways, backward or forward, I smile through the pain, if possible, and laugh through the indignity.

“Nice,” I say. “Thanks.”

Politeness has a place in judo, too.

Besides, I’ve been anxious since I started practicing a few months ago at the Jason Morris Judo Center to keep on everyone’s good side.

They take students of all ages and abilities at the Judo Center — my presence proves that — but much of the crew is young and strong and skilled.

Several are in the top ranks of judo players, nationally and internationally, and they sometimes look quizzically at a middle-aged guy trying not to trip over his own backpedaling feet.

A couple of times, I have caught Morris flashing them a look that says, “Don’t kill him.”

Other times, he has just said it.