Would be good to know what sort of THR you have before encouraging youbyo try running again. I went for a metal on metal resurfacing on my left hip 6 years ago because (like Andy Murray) I wanted to stay active in running, climbing and mountaineering. Metal does wear out, slowly, but I was 64 and it did not have to last 40 years… Was jogging at 6 weeks, carefully, and built up over the next year to decent pace up to 10k plus long days in the hills. Right hip is 3.5 years old, bone not good enough for a resurfacing, and is ceramic on ceramic. Surgeon assured me I would not break it, carry on doing what I do. Running again at 6 weeks, have run up to 13 miles and walked 42 in the hills, joint is perfect. Rest of me is aging rapidly but I can run every day if I go steadily enough.
If you have a plastic lined bearing then wear might be a problem eventually, although the latest cross-linked polyethylene liners may be even better than ceramic as they cannot shatter like old ceramic did occasionally (just had an acquaintance undergo replacement for broken ceramic bearing) but if you are light and efficient then running should not be risky in my opinion.