Nay (kind of) wrote:
This thread is off the rails. The OP asked about strength training for “competitive” masters.
For a 5k, that is generally going to be in the 16-17 minute range for 40+ and 17-18 minute range for 50+
To train to that level at those ages, you can’t do most of the routines described in most of the posts. The routines are about health and fitness, not performance.
If you want to run fast as an old guy, you have to prioritize running. Your S&C has to be limited to the bare minimum to prevent longtime injuries from getting in the way.
Most of the stuff in this thread is worthless for a master trying to perform at a high level. That master is better off running more, not doing heavy squats and deadlifts.
As a competitive masters runner nearing 50, I have prioritized running for many, many years, and within the last year I've added strength training 2-3/week. That includes squats and deadlifts once or twice a week with supportive exercises once a week, as well.
I've found that strength training has allowed me to train at a high level and kept longtime injuries from getting in the way.
I would highly recommend strength training for competitive masters runners. That should include heavier squats and deadlifts. Like any other aspects of the OP's training (mileage, workouts), the trick is to not overdo it. Strength training shouldn't be detrimental to the running, but it definitely can be worked into competitive master runners schedule. I believe masters runners are leaving something on the table if they're not incorporating strength work (especially heavier lifts) into their program.
OP, you need to figure out what works for you, but I'm a big believer that it should be a "yay".