This is not the 'how to avoid pantyline' question. This is the how to avoid sore seatbones/blisters question. I lost a little weight, and this summer has been rather agonizing in that too much dressage seems to give me bruises, bumps, and blisters. Sitting in a wood chair after riding is torture. I have tried long-line types of underwear thinking it was the seams and they did help, but lack of padding might be the issue since I wasn't having this problem before I lost weight, or this winter when i was wearing thicker and/or insulated breeches. Any recommendations? I'm using the same saddles I've had for years, and on the same horses.
(other than more jumping, less flatwork.... I've thought of that)
There are undies with padding for riding for timhis purpse. Look in the catalogs, esp the dressage catalogs. (I have no need for extra padding, sorry to say) Also review your position. If you are truely sitting on your "triangle" in theinco saddle that is not what you sit on in a chair. Unless you are riding a more "chair seat" position than you realize. And that incorrect position is so called by that name for a reason.
What I found works for me - ditch any baggy breeches and tighten up your belt (extra fabric movement from your breeches doesn't help matters). The Lacey thongs from VS that everyone raves about are perfect for dressage (they don't chaff or ride up) and invest in some Body Glide and apply to seat bones when getting dressed.
What worked for me was tighter breeches, ditching the full seats, and Patagonia underwear. Any cut is fine. Seems to be the fabric and lack of binding that works for me. They're pricey but they last forever. Totally worth it.
I have the same problem, especially in the summer when I sweat all day long and my skin gets more sensitive. I found that wearing silky shorts (the kind that looks like bicycle shorts but are sold in the under-garment section) under my breeches and over my hanes helps. For me it's lack of cushion and the friction that rubs holes in my seat bones. This should help if that's what causes yours' harm as well. Good luck.
An old fashioned and very cheap solution: try talcum powder. I use it when riding in hot conditions and I rub a little onto my skin at the edges of my underwear or where any rub might happen. It is then very easy to carry extra to top up when needed. Try it on your seat bones. I also avoid full seat breeches becaue they rub after a couple of hours, no matter how old and broken in.
Riding in Italy one time, we had a slightly disasterous day that meant we were in the saddle for hours under a really hot sun. One of the men riding got the worst pressure sores I have ever seen from his full-seat breeches and a saddle that was too small for him
If it's chafing during summer due to sweat, then Body Glide and talcum (such as Anti-Monkey-Butt) powder will take care of it. It it's lack of padding on seatbones, then a different saddle will help (Antares, for example, has several different seat widths among their options to fit the rider, which can be combined with the tree size that fits the horse). Temporary fixes include padded bicycle shorts and/or padding for the saddle like Cashel or sheepskin seat savers. I wish you luck resolving this quickly, it's not much fun.