Playing around with reasonable equation to track over time...
Fitness score = [age / (max BP for 5 reps in lb)] x 20 + 1 mile run time in min
Lower score is better
Example for fit 50 year old:
50 / 315 x 20 + 7.5 = 10.7
Example for not so fit 50 year old
50 / 100 × 20 + 15 = 25
Obviously...