It's not good when using hired skates and the serrated front digs in when going at pace. I'm thinking it's how I tore the muscle in my shoulder now as it's the only trauma I've had
I started off with strap-ons (ooooh errrr) strapped to my shoes, which at the time were these:
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In a weird loop, I also ended up making folding ice skates for the Dutch skating team ni my younger days. Only did it for a few months but it was still a very interesting thing to do.