Running for over 30 years, injury-free from age 30 to 62(multiple marathons & trail endurance), I had four surgeries on the L ankle/foot, then four on the R knee due to a fall & non-healing patella fracture(total knee & hip replacements), between 2011 & 2018. From atrophied quads to hot spots on the soles of both feet, it's been a nightmare.
December 2018 a podiatrist friend suggested the Protalus inserts because Dr. Comfort & SuperFeet inserts were not helping with comfort or stability. WOW! What a significant difference ~ improvement ~ with Protalus; my Ortho surgeon & his prosthetist and my regular Podiatrist are impressed with the materials, the design & the comfort I report (less incidence of calluses or severity of painful hot spots).
Hey, the proof is in the product and I'll continue with Protalus because it does what is needed to help me walk, ride a bike, exercise and even sleep better every day.