Today is the hardest session in the 5-Day Challenge. It’s short, intense, and rewarding—you’ll finish with a real sense of accomplishment.
About Zone 4
Zone 4 is HARD INTENSITY. You will push above and beyond “race pace” (you should only be able to hold this effort for 5 minutes maximum if you had to).
You’re in Zone 4 when:
- Your breathing is heavy and rapid, and you are becoming short of breath.
- Speaking even single words is difficult.
- Watch my Zone 4 demo video [1 min]
Why Zone 4? Zone 4 training increases VO2 max via heart adaptations by challenging the heart to pump more blood at a higher rate. It will be tough, but the workout will leave you with a great sense of accomplishment and well being. This workout will make you faster.
Instructions:
You can do this workout as running, rollerskiing, ski walking, mountain biking, on skiErg, on a rower, or swimming or cycling. Find a mode that will make it challenging, but doable for you. If cycling, choose climbing terrain to ensure you stay in zone (avoid long downhills within intervals). Feel free to extend this duration if you have the available time.
⭐️ Workout Goals:
1) Develop VO2 max via heart adaptations by challenging the heart to pump more blood via a higher heart rate.
2) Practice pushing above and beyond race pace (you should only be able to hold this effort for 5 minutes maximum if you had to)
Workout Options – Pick One
✅ SAFER: Best for those easing into training, getting over a recent sickness or injury, or anyone wanting an easier option.
✅ STANDARD: A great choice for the majority of people.
✅ ADVANCED: Suitable for well-trained, resilient athletes with more time for training.
| SAFER | 🔷 WARM UP | 🔷 WORK | 🔷 COOL DOWN |
| 3-4 x 90 sec hard / 3min recovery | 15-30 minutes (personalize this to your time availability and needs; you are looking for an elevated heart rate, warm muscles, and sweating). | 3-4 reps of 90 seconds hard, 3 min easy. Start with 3 repeats and add 1 more at the end if you still feel it’s doable and you’re not gassed completely. | 5-10 minutes very light exercise as needed to return to pre exercise baseline (gradually reduce pace to walking speed). Feel free to extend the workout time after the intensity, for as long as you like. |
| STANDARD | 🔷 WARM UP | 🔷 WORK | 🔷 COOL DOWN |
| 3x3min hard / 3min recovery | 15-30 minutes (personalize this to your time availability and needs; you are looking for an elevated heart rate, warm muscles, and sweating). | 3 reps of 3 min hard, 3 min easy. Start with 3 repeats and add 1 more at the end if you still feel it’s doable and you’re not gassed completely. | 5-10 minutes very light exercise as needed to return to pre exercise baseline (gradually reduce pace to walking speed). Feel free to extend the workout time after the intensity, for as long as you like. |
| ADVANCED | 🔷 WARM UP | 🔷 WORK | 🔷 COOL DOWN |
| 5x3min hard / 3min recovery | 15-30 minutes (personalize this to your time availability and needs; you are looking for an elevated heart rate, warm muscles, and sweating). | 5 reps of 3 min hard, 3 min easy. | 5-10 minutes very light exercise as needed to return to pre exercise baseline (gradually reduce pace to walking speed). Feel free to extend the workout time after the intensity, for as long as you like. |
Workout Resources:
Zone 4 intensity effort demo video from Coach Dasha
Zone 4 Guidelines
