seeing this come up a lot in HRT threads, worth pulling apart because the framing matters for what you do next. the claim that estradiol “causes” plantar fasciitis isn’t well supported by the literature i’ve seen. what is documented: estrogen receptors are present in plantar fascia tissue, and there are observational studies linking the perimenopausal estrogen decline to higher rates of fasciitis, tendinopathy, and frozen shoulder. the mechanism people usually invoke is collagen turnover and reduced tissue compliance. so the more defensible framing is that low estrogen is the risk factor, and HRT is the timing coincidence, not the cause. where it gets messier: - progesterone formulations matter. switching from a synthetic progestin to micronized progesterone is a real change in what’s circulating, but the connective tissue effects of progestins specifically are not well characterized. “i changed it and the pain stayed” doesn’t rule the formulation out, it just means 4 months isn’t long enough to see the answer.
- transdermal vs oral estradiol changes IGF-1 and SHBG in different directions. oral suppresses IGF-1 more, which matters for collagen. if you’re on oral, worth a conversation about switching delivery route.
- weight training while painful can absolutely aggravate fasciitis if you’re loading through a compensated gait. seated/prone is smart but check that your calves aren’t getting neglected, soleus loading is the boring answer most people skip. the thing i’d push back on gently: “i never had it my whole life, therefore HRT.” you also never had perimenopausal estradiol levels your whole life until recently. the underlying tissue environment changed before the HRT started. HRT may be insufficient dose, wrong route, or just not fast enough to reverse two years of collagen changes in 4 months. worth getting an US to confirm it’s actually fasciitis and not a partial tear, because the management diverges.