By Terri Rejimbal, RRCA Certified Coach
If you’re like most runners, you want to run further and faster. We fill our training weeks with track workouts, easy running and long runs. What if I told you there’s a workout you can add to your arsenal that will help improve your VO2 max so you can run with less effort?
What is VO2 max??
VO2 max is defined as the “maximal capacity for oxygen consumption by the body during exertion”. Simply stated, it’s how much oxygen your body uses during exercise at maximum effort. VO2 max is measured as maximum milliliters of oxygen consumed in 1 minute / body weight in kilograms and is generally considered the best indicator of cardiovascular fitness and aerobic endurance. The higher the number, the more oxygen your body can take in and deliver to your muscles thereby, enabling you to run faster. Factors such as how many red blood cells you have, how conditioned your muscles are to distance running, and how much blood your heart can pump, all play a role. Elites can have a high VO2 max, but not be fastest or the most efficient.
While VO2 max is genetically pre-determined and will decline as you get older, you can improve your running efficiency through Lactate Threshold (LT) training. Jack Daniels, Ph.D., investigated changes in VO2 max and despite VO2 max leveling off, running performance continued to improve with training.
The lactate threshold, also referred to as anaerobic threshold, is the point during all-out exercise in which lactate builds up in the bloodstream faster than the body can remove it. Basically, you’re redlining in that aerobic/anaerobic state during activity. LT pace for the average 40-min 10K runner is 75-80% of MHR. For elites/highly trained runners, it is about 85-90% MHR. LT pace feels “comfortably hard”.
This is one of my favorite LT workouts. It’s simple and when done correctly, it’s efficient and effective:
Warm-up for 10 minutes or 2 miles then run 3 minutes at VO2 max pace (just faster than 5K pace). Recover for 2 minutes at 80-85% of your heart rate (HR) or roughly 2-2.5 minutes over your VO2 max pace. Repeat 4-6 times, working up to a max of 9-11 reps.
You know you’re improving when you can reach your VO2 max pace within 60 seconds at the onset of the 3 minutes, your recovery heart rate at 80-85% feels comfortable, and you’re breathing normally.
How often should you do LT training? Anywhere from 3-12miles a week or 6-15% of your weekly total mileage depending on your training plan. LT training workouts are intense so make sure you allow enough time to recover in between LT workouts.
Keep in mind that training faster than LT pace provides less stimulus to improving your LT because you’re relying more on an anaerobic lactic-acid system that isn’t sustainable for long periods before you’re forced to stop. Likewise training slower than LT pace doesn’t provide enough stimulus gains to take effect, either.
Any workout done regularly and that places a higher, continuous demand on the cardiovascular system can increase your VO2 max. The key is to work at an intensity right below your anaerobic threshold (the point at which you start feeling lactic acid build in your working muscles), and you should exercise at this level of exertion for at least 15 minutes.
Terri Rejimbal is a competitive Masters athlete, a 3-time winner and 8-time Masters champion of the Gasparilla Distance Classic half-marathon; 6-time Disney Masters marathon winner, 6-time Florida USATF Athlete of the Year, and a New Balance product tester. Terri is a RRCA certified running coach. Contact Terri at firstname.lastname@example.org, on Facebook/terri.rejimbal, Twitter @trejimbal, or Instagram @bayshorerunner.