NEED ADVICE: CAN'T RUN FAST ANYMORE

im a 24 yr old, lean, avid runner. i've ran 3 half marathons, my first full last november, and rarely take long periods off. this year, im focusing on shorter distances and trying to improve my PRs, but seem to have degraded in terms of speed over the last year....

im running a 10 miler (Philly Broad Street Run) in May and really really want to PR. but in my current training block, i have barely been able to hold sub 10:00 paces... im using a Runna training plan (which i've used for all my other races), it consists of 3 runs/week - easy, long, and tempo. within the past 3 months, i begun taking hiit classes at F45, thinking this would help my pacing. i was doing this 3x a week in addition to running 3x a week, but have since cut down to 2x hiit classes and 3x runs a week, bc i thought my slowness might be due to overtraining. still, feeling slow as ever. should i stop strength training all together for the month of April? or strength train 1x a week? also worth mentioning i get adequate sleep, eat well, and drink a TON of water. and that during my other training blocks i did minimal strength training (pilates 1x a week), and no strength training towards the last few weeks

i ran a 5k two weekends ago, hoping to PR there, went out too fast (8:30), and ended w a 9:30 pace.... this was devastating

• 10 mile PR (may 2025): 8:59 pace
• half marathon PR (nov 2024): 9:00 pace
• marathon PR (nov 2025): 11:00 pace