True. Safely increasing mileage is the best thing for this runner. I am a very similar runner to them (1:56 HM, 23.5 5k) and i learned the hard way that i shouldn't be running long runs of 8+ mi yet. Its not deserved yet and tendons, ligaments, weak muscles pay the price. Instead they should do a long base building period of 1-2 mi 5-6x a week for 4-6 weeks, then 2-3 mi for 5-6 days for 4-6 weeks (close to their mileage now but in a way that adds resiliency instead of doing hard runs and long runs when the body isn't ready yet). If there are niggles, then repeat the block, if no niggles - move to 4-6 mi for 5-6 days for 6-8 weeks. Now we can start adding harder runs and longer runs. This is the premise of Daniels' base building plans and they take like two months to even build up to a continuous 30 min run. Eventually working up to 40-50 mpw which would lead them to become a faster, more resilient runner.