Reply To: 100 Pace by 50's
Obviously there’s little value in doing 2-3 reps. You’re on the right track with more rest. If you’re getting 4.5-6 x race distance at race pace (not including the failed attempts, which are still valuable), that’s about as much as you can expect from a single set, so it looks like you have the right interval.
If you’re targeting (100 race time)/4, I’d suggest instead you target average 2nd 50 race split. That should be a little slower, so maybe you can dial back the interval to 1:05 or even 1:00 and still get into the mid teens for reps before failing out.