Parkrun: Does a warm up actually make any difference?

MARM returns to the parkrun that was cancelled last weekend, with the intention of setting a PB in the searing heat. To do it, he decides he’s going to warm up “properly”. Will it make any difference? Does he even know what he’s doing?? And will the MARM Mobile 2.0 Galaxy have a winning start? #marmyarmy #parkrun #parkrunchallenge #warmup #running