I didn't say she wouldn't improve. Let's say a 14 year old guy runs a 20 minute 5k, he'll have trouble breaking 16 before the end of HS unless he really hasn't been running much or has a late growth spurt.
If a 14 year old girl has a 23 minute 5k, a 3 minute improvement (1 minute less than the male) isn't an unreasonable estimate.
If a 14 year old girl has a 23 minute 5k, a 3 minute improvement (1 minute less than the male) isn't an unreasonable estimate.