I think this is one of the biggest mistakes people make once they start paying attention to running numbers.
You have an easy pace.
The watch says you are seven seconds slower than it.
So you speed up.
Now you are three seconds faster.
That feels pretty good, so you keep going.
Half an hour later your easy run is basically a moderate workout nobody asked for.
Great.
You beat your easy day.
The pace has a job
That is the whole reason I like pace zones.
Easy pace has a job.
Threshold pace has a job.
Interval pace has a job.
You are not supposed to make every one of them as fast as possible.
Lifters already understand this.
If I am warming up for a heavy bench session, I do not turn the empty bar into AMRAP work because it felt light.
That would be ridiculous.
But people do the running version of that all the time.
Your pace needs to come from your fitness
A 7:30 mile could be easy for one runner and completely unrealistic for another.
Same pace.
Different workout.
This is why generic pace charts only get you so far.
I would rather start with something that actually reflects current running fitness. A recent race, time trial, or enough recent training data to make a reasonable estimate.
Then you can build paces around that.
Easy.
Moderate.
Threshold.
Intervals.
Faster repetition work.
Now the numbers actually belong to the runner using them.
Even then, the pace is not law
This matters.
Say your easy pace normally lands around 9:15 per mile.
Today it is 85 degrees.
You slept badly.
And yesterday was a hard squat day.
If 9:15 feels noticeably harder than normal, forcing the pace because the app said 9:15 is missing the point.
Slow down.
The workout was supposed to be easy.
That matters more than making the average pace look pretty.
Easy running should feel almost suspiciously easy sometimes
Especially if you come from lifting.
In the gym, hard work is obvious.
A heavy set feels heavy.
Your legs shake.
The bar slows down.
Nobody needs to convince you that the set counted.
Then you start running and an easy 30 minutes barely feels like training.
So you speed up.
I understand the temptation.
Leave it alone.
The whole point is that you can recover from it and still have something left when the actual hard sessions show up.
Moderate pace is not bad
This gets oversimplified too.
There is nothing wrong with moderate running.
There is something wrong with accidentally turning every easy run into moderate running.
Those are different things.
If Tuesday is supposed to be easy and becomes steady because you felt good, no big deal once.
Then Friday does the same thing.
Now your legs have done two harder sessions than the program planned before you even reach the interval workout.
That adds up.
Lifting changes the math
This is the part I care about most for Mass in Motion.
A running-only program can look at the running week and decide where the hard sessions belong.
A hybrid program cannot stop there.
Heavy squats matter.
Deadlifts matter.
High-volume lower-body work matters.
A threshold run needs to fit around that stuff.
Otherwise you end up with a perfectly reasonable running schedule and a perfectly reasonable lifting schedule that become a terrible program once they are put together.
Monday: heavy lower.
Tuesday: hard run.
Wednesday: more lower-body volume.
Thursday: intervals.
Then somebody wonders why their legs feel awful by Friday.
The pace zones were not the problem.
The week was.
Pace zones should move when you move
This is another thing I do not like.
You run a 5K.
Training paces get calculated.
Then six months later you are still using the same numbers even though your fitness changed.
That makes no sense.
If you got faster, the paces should probably move.
If you took time off, they may need to come back down.
Same thing we already accept with lifting.
If your squat goes from 405 to 455, you would not keep pretending your training percentages should be based on 405 forever.
Running should work the same way.
The number should follow the athlete.
Not the other way around.
If you are adding running to lifting, start with Running for Lifters or Zone 2 Running for Lifters.