More Intervals to increase speed and pace.
10:00 fast/ 3:00 slow or rest X 5
This is designed to get uncomfortable. You are trying to go faster than a 30 min slow steady pace. Just right under threshold. Go to the point that you are not sure if you can maintain the pace. If you have to stop and can’t make it for 10 min., that’s fine. I’d rather you try something that is out of your wheel house than play it safe.
The slow steady pace days are the days you need to play it safe. I would rather you go slow on those days