Is this mileage progression gradual enough? I have experience around 50 mpw with a 3-4 mile "threshold" workout that throughout the cycle progressed in intensity enough to eventually became a VO2 Max workout, at which point my fitness began to regress. Also some experience around 50-60 mpw with a VO2 max workout, 5k race, continuous tempo, 12 mile long run, which in hindsight was a a decent amount too much and not sustainable. It also might be useful to note that I now have the opportunity to slow down my easy runs.
6/1/25: 25
6/9/25: 40, 8 long run
6/17/25:40, 8 long run
6/24/25: 45, 4 LT1, 9 long run
6/30/25: 45, 8 LT1, 9 long run
7/7/25: 45, 8 LT1, 9 long run
7/14/25: 45, 8 LT1, 9 long run
7/21/25: 45, 10 LT1, 9 long run
7/28/25: 45, 10 LT1, 9 long run
8/4/25: 45, 10 LT1, 9 long run
8/11/25: 45, 10 LT1, 9 long run
8/18/25: 50, 12 LT1, 10 long run
8/25/25: 50, 12 LT1, 10 long run
9/1/25: 50, 12 LT1, 10 long run
9/8/25: 50, 12 LT1, 10 long run
9/15/25: 50, 12 LT1, 10 long run, xc race?
9/22/25: 50, 12 LT1, 10 long run
9/29/25: 50, 12 LT1, 10 long run
10/6/25: 50, 12 LT1, 10 long run
10/13/25: 55, 14 LT1, 11 long run
10/20/25: 55, 14 LT1, 11 long run
10/27/25: 55, 14 LT1, 11 long run
11/3/25: 55, 14 LT1, 11 long run
11/10/25: 55, 14 LT1, 11 long run
11/17/25: 55, 14 LT1, 11 long run
11/24/25 55, 14 LT1, 11 long run turkey trot?
12/1/26: 55, 14 LT1, 11 long run
12/8/26: 55, 14 LT1, 11 long run
12/15/26: 55, 14 LT1, 11 long run
12/22/26: 60, 15 LT1, 12 long run
12/29/26: 60, 15 LT1, 12 long run
1/5/26: 60, 15 LT1, 12 long run
1/12/26: 60, 15 LT1, 12 long run
1/19/26: 60, 15 LT1, 13 long run
1/26/26: 60, 15 LT1, 13 long run
2/2/26: 60, 15 LT1, 13 long run
2/9/26: 60, 15 LT1, 13 long run
2/16/26: 60, 15 LT1, 13 long run
2/23/26: 60, 15 LT1, 13 long run, track race?
3/2/26: 65, 16 LT1, 14 long run
3/9/26: 65, 16 LT1, 14 long run
3/16/26: 65, 16 LT1, 14 long run
3/23/26: 65, 16 LT1, 14 long run
3/30/26: 65, 16 LT1, 14 long run, track race?
4/6/26: 65, 16 LT1, 14 long run
4/13/26: 65, 16 LT1, 14 long run
4/20/26: 65, 16 LT1, 14 long run, half marathon?