During our off season period (now) my team train boxing every Sunday, it's very fun but we do it to keep in shape so there's not so much focus on the sport itself like different punches in different situations. I like to watch UFC for example and I've been thinking about training MMA but in that case more for fun because sometimes the submissions looks really nasty

but I think my american football is enough with hard hits

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I would recommend martial arts, it keeps you in shape and all the grabs, kicks and punches might come in handy

. My favourite martial art is MMA.
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