Muscular endurance treadmill workout

I love running on the treadmill and I love cycling on my indoor bike trainer.
Perhaps my love of indoor "stationary" workouts comes from following a black line for 25 yards in for 23+ years as a competitive swimmer.

I enjoy being able to control my workout when I train indoors and to minimize all outside influences like terrain, traffic, wind and cold/hot weather.
But I also love training outside as this is the best environment for me to mentally and physically prepare for my upcoming races.

It's easy to make excuses when it comes to weather and available time to train (morning and night) so for me, I always seek the best environment for a quality workout. Sometimes it is indoors and sometimes it is outdoors.
At time in the year, most of my workouts are indoors - but as soon as it gets warmer, it's hard for me to stay indoors to train. I love the sun and the heat!  

Karel, on the other hand, will make every attempt to train outside, as much as possible. 

For my run workout this morning, the focus was endurance but there was also a heavy strength component. 

My key runs often include a very specific main set whereas my optional and/or EZ runs are form focused and pace and miles are not a priority.

If you are one to despise the treadmill, I challenge you to my run workout as I hope that you love the structure as much as I did as you feel yourself staying focused on each segment and determined to finish all three rounds.

I strongly advise having a pre-workout carb snack before this workout (I had some oatmeal with raisins, cinnamon and honey), at least 1 bottle water (and a gel or energy chews/blocks in case you need a pick-me up in the last round) and a post workout snack/meal with protein and carbs as soon as you can to start the rebuilding. 

I suggest to pace yourself and to go by RPE. This is an endurance focused run so you shouldn't be taxing the heart too much. Your muscles are designed to get tired but not at the expense of your heart working excessively hard.
Keep the effort steady and strong. 

With every segment of the main set, you will have the opportunity to get the HR up a little by increasing the speed and when you run at an incline, this should make you feel powerful. When you finish an incline run and return to 1% grade, this should feel like a slight recovery.

Imagine yourself running up and down hills with a little hard effort before and after each climb. 

Try to keep the same speed throughout the entire round, but adjust if your form starts to suffer. You are better off adjusting your pace, than calling it a day, if you find you were over-ambitious with your intensity at the start of this workout. 

Happy running!
5 min Dynamic warm-up

15 min jog warm-up (very EZ, light on the feet)
10 min power walk at 15% incline, fast walk (ex. 3.5 mph)

MS 3x's:
3 min at 1% incline (last 30 sec strong)
3 min at 4% incline (last 30 sec strong)
3 min at 1% incline (last 30 sec strong)
3 min at 4% incline (last 30 sec strong)
3 min at 1% incline (last 30 sec strong)
30-60 sec break (straddle treadmill and lower HR as much as possible)
Repeat 2 more rounds

Walk to cool down

(if you are not comfortable performing this all running, you could also use this as a walking workout).

Modification if you are short on time:
5 min Dynamic warm-up
5 min jog warm-up
10 min power walk (this will wake-up your glutes)
2 rounds of the main set instead of three - still keep with the same focus and intensity.