Oh the irony, as a 'flat lander' hills have always been a huge weakness, I feel like I'm going backwards most of the time when I run up hill. However, it seems hills are what have kept me running these last 6 months, not just the HRT. Going back to doing more runs on the flat has really aggravated my hamstrings. They get super sore and tight and are certainly not interested in racing parkruns. However, when I go back to running on short, steep rocky hills, the hamstrings stop complaining. Case in hand, I ran a hilly 21.3 km last weekend and it went pretty well all things considered. It was further than planned, but I didn't suffer any serious consequences from the run (except for a couple of unhappy toenails from the downhills!). It is unclear why I am overloading the hamstrings on the flat, it could be to do with muscle weaknesses elsewhere such as the glutes and core. So I am currently consulting with someone on how to correct these imbalances and see if I can banish tired and tight hamstrings. Only time will tell. Watch this space.