When it comes to training, there are roughly a dozen different types of running workouts that make an appearance in your plan.
From track intervals to threshold workouts, hill sprints to tempo runs, running coaches and exercise physiologists have developed a relatively extensive library of workouts, each designed to offer specific and unique physiological and psychological benefits to improve running performance.
One of the less commonly referenced running workouts is critical velocity training, also called CV running for short. While fewer coaches and runners actively use the term critical velocity training in their training programs, a surprising number are actually unknowingly performing these workouts.
Critical Velocity (CV) Training is a pace-based method that improves aerobic capacity, lactate clearance, and endurance, targeting the fastest pace a runner can sustain for 30-40 minutes, falling between lactate threshold and VO2 max pace.
I’ve put together a comprehensive guide to CV running, designed to introduce runners to this effective method and provide actionable tips on how to incorporate CV workouts into their training program.
What is Critical Velocity Training?
Critical Velocity training, is a training method created by American Tom “Tinman” Schwartz while working as an assistant coach at cross-country and track programs at the University of Wisconsin-La Crosse. Tom Schwartz defined critical velocity as a “somewhat hard” pace that distance runners can sustain for half an hour.
Therefore, critical velocity training involves any running workout done at a pace that the runner can hold running at maximal effort for 30 minutes. In this way, CV running can be equated to how threshold training involves any workout where threshold pace is used, keeping in mind that threshold pace can be sustained all out for an hour of running.
Critical velocity is thus a harder effort than threshold effort but easier than 5K race pace for most runners. CV running can be equated to an effort level around 90 percent of your VO2 max.
In contrast, the lactate threshold occurs around 83-88% of your VO2 max.1Cerezuela-Espejo, V., Courel-Ibáñez, J., Morán-Navarro, R., Martínez-Cava, A., & Pallarés, J. G. (2018). The Relationship Between Lactate and Ventilatory Thresholds in Runners: Validity and Reliability of Exercise Test Performance Parameters. Frontiers in Physiology, 9(1320). https://doi.org/10.3389/fphys.2018.01320
Therefore, your threshold run pace would be the pace you are running at 83-88% of your VO2 max, which is why you can sustain threshold pace for an hour and critical velocity running pace for only 30 minutes.
How Is CV Training Effective?
Schwartz has primarily credited the fitness improvements from critical velocity training to the improvements it induces in the aerobic capacity of Type IIa muscle fibers.
In exercise science, type IIa muscle fibers are fast-twitch fibers with the specific property of being very adaptable. They can be manipulated through specific training2Galpin, A. J., Raue, U., Jemiolo, B., Trappe, T. A., Harber, M. P., Minchev, K., & Trappe, S. (2012). Human skeletal muscle fiber type specific protein content. Analytical Biochemistry, 425(2), 175–182. https://doi.org/10.1016/j.ab.2012.03.018 to function in a certain way.
If you do a lot of sprint training, for example, these muscle fibers can function more like type II fast-twitch fibers. If you do more aerobic training and sustained effort like CV running workouts, the type IIa muscle fibers can become more efficient at extracting and consuming oxygen.
In turn, these adaptations will help you sustain harder efforts for longer distances without producing the fatiguing byproducts of glycolysis and anaerobic metabolism, meaning that you can sustain a faster “hard cruising speed” using cruise intervals.
The benefits of CV running for endurance athletes include the following:
- Increase oxidative capacity of Type IIa muscle fibers
- Improve aerobic metabolic capacity at harder efforts
- Increase cardiovascular fitness
- Build mental strength at “comfortably hard” paces
- Reduce stress on the body relative to VO2 max intervals
Does Critical Velocity Training Really Work?
While there is still a relative lack of scientific evidence specifically investigating the effectiveness of CV running, there is plenty of anecdotal evidence to suggest that these workouts can improve distance running and triathlon performance.
For example, in 2019, Schwartz implemented CV running into the training programs of athletes he coached, three of which met the World Athletics Championships 5000m qualifying standard of 13.22.50, including Sam Parsons from Germany, Jordan Gusman from Malta, and Drew Hunter from the US.
Another standout using CV running is professional triathlete Morgan Caldwell Pearson from the USA.
Examples of Critical Velocity Running Workouts
Eager to give critical velocity training a try? Here are a few CV running workouts:
#1: Fartlek-Style Critical Velocity Training Workouts
You can skip the track altogether for these workouts and pick your favorite running loop, roads, trail, park, treadmill, or otherwise.
- Warm up for 2 miles jogging at an easy pace
- 5–7 x 3 minute at critical velocity training pace with 1 minute jog recovery in between each
- Followed by 5 x 45 seconds at mile pace
- Cool down for 1 mile at an easy pace
Here is another fartlek option:
- Warm up for 2 miles jogging at an easy pace
- 16 x 1 minute at critical velocity training pace with 1 minute jog recovery in between each
- 6 x 30 seconds at mile pace
- Cool down for 1 mile at an easy pace
Or, try this challenging CV workout:
- Warm up 2 miles jogging at an easy pace
- 5-6 x 5 minute at critical velocity training pace with 90 seconds jog recovery in between each
- 6 x 30 seconds at mile pace
- Cool down for 1 mile at an easy pace
#2: Critical Velocity Training Workout for Runners Trying to Break 22 Minutes in a 5K
- Warm up 2 miles jogging at an easy pace
- 5 x 1km at in 4:30/km (7:14.52/mile pace) with 200m jog recovery in between each
- 6 x 200m accelerations, starting at 5k pace and ending each acceleration at 800m pace
To adjust for a faster or slower pace, use the calculator on Schwartz’s website here.
#3: Beginner CV Running Workout
Here is a critical velocity training workout for beginners:
- Warm-up 1 mile jogging at an easy pace
- 8 x 1 min repetitions at CV running pace, 90 seconds recovery jog or walk
- 4 x 15 seconds sprint reps with full recovery
- 1 mile cool down jog
CV Running Workout Progression
Like any other type of running workout, critical velocity training workouts should progress in difficulty over time as you get fitter and more accustomed to handling CV training pace.
Here is an example of an eight-week progression of critical velocity training workouts:
- Week 1: 12 x 400 meters reps at CV pace with 90 seconds recovery
- Week 2: 6 x 800 meters reps at CV pace with 90 seconds recovery
- Week 3: 5 x 1,000 meters reps at CV pace with 90 seconds recovery
- Week 4: 5 x 1,200 meters reps at CV pace with 90 seconds recovery
- Week 5: 5 x 1,000 meters reps at CV pace with 60 seconds recovery
- Week 6: 5 x 1,200 meters reps at CV pace with 60 seconds recovery
- Week 7: 2 x 1,600 meters at CV pace with 90 seconds recovery, 2-3 x 1,000 meters at CV pace with 60 seconds recovery
- Week 8: 4 x 1,600 meters reps at CV pace with 90 seconds recovery
Note: Follow each workout with 4-6 repetitions of fast strides or accelerations, 50-200 meters each.
Ready to give CV training a try to prepare for your next half marathon, marathon, or ultramarathon? Let us know how it goes!
If you would like to read into adding other types of running workouts to your training plan, check out our hill sprint guide:
