Hello everyone, I am new to the site as I am hoping to get advice on a few problems I have while running recently. I am well into my first marathon training to which I am following a strict plan. However approx. 4 weeks ago I started to develop quite severe blisters on my right foot insole arch. My current running trainers were Brooks at the time which I had done well over 500 miles in so I thought a fresh new pair of running shoes would help the situation. On recommendation I bought the latest ON cloudflow supportive running shoe. My first 3 runs (averaging 15 miles) were perfect and no blisters but now the blister has returned with a vengeance. My latest run (yesterday) I used a very expensive blister plaster and wrapped my foot in a breathable bandage but still managed to aggravate the blister after 13 mile and made running impossible. I have approx. 10 weeks left of training and am very concerned that if I don't sort this problem I may have to pull out of the marathon. Please has anyone got any suggestions? Many thanks for reading.