How to Improve the 3 Running Thresholds (Z2, LT, and VO2 Max), with Phil Batterson, PhD
Release Date: 08/28/2025
The Strength Running Podcast
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info_outlinePhil Batterson is a competitive runner, former running coach, and the founder of Critical Oxygen. Phil has a PhD in human bioenergetics and a love for all sorts of endurance sports, from rowing to track and field and ultras. His goal with Critical Oxygen is to teach athletes and coaches how to optimize their physiology to maximize endurance performance.
This episode is important and is a repost of episode 330 from 2023.
Phil breaks down some of the complex physiology behind the three different thresholds to make it more accessible, as well as providing practical ways to apply it in training. Some of our discussion includes:
- Phil’s journey into endurance training and exercise science
- What physiology defines each of the three thresholds
- How runners can determine their own thresholds
- The importance of lactate threshold work for race preparation
- Common mistakes when using training zones
- How to integrate VO2 max work with cross training
Whether you like to geek out on physiology or just want to race faster, you'll learn a lot from my conversation with Phil!
Links & Resources from the Show:
- Follow Phil on Instagram
- Check out the Critical Oxygen podcast and blog
- Let me help you get the most out of your training
Thank you to 2Before!
We are supported by 2Before, a powerful sports supplement made from New Zealand Blackcurrants designed to increase endurance, manage inflammation, support immunity, and promote adaptation. 2Before helps to boost performance by increasing blood flow, making it more efficient for the body to pump oxygenated nutrient-rich blood into the muscles.
Just like beetroot but more effective, blackcurrant berries are vasodilators, helping you get more blood flow to where it's needed.
Boost your performance and immune system with 2before: use code JASON for 30% off 20 packs and multi-serve packs at 2Before.com.
Thank you to 2Before for supporting Strength Running!
Thank you LMNT!
A big thanks to LMNT for their support of this episode! They make electrolyte drinks for athletes and low-carb folks with no sugar, artificial ingredients, or colors. They are offering a free gift with your purchase at LMNT. And this does NOT have to be your first purchase. You’ll get a sample pack with every flavor so you can try them all before deciding what you like best.
LMNT’s products have some of the highest sodium concentrations that you can find. Anybody who runs a lot knows that sodium, as well as other electrolytes like magnesium and potassium, are essential to our performance and how we feel throughout the day.
If you’re not familiar, LMNT is my favorite way to hydrate. They make electrolytes for athletes and low-carb folks with no Sugar, artificial ingredients, or colors. I’m now in the habit of giving away boxes of LMNT at group runs around Denver and Boulder and everyone loves this stuff.
Boost your performance and your recovery with LMNT. They’re the exclusive hydration partner to Team USA Weightlifting and quite a few professional baseball, hockey, and basketball teams are on regular subscriptions. So check out LMNT to get a free sampler pack and get your hydration optimized for the upcoming season.
Thank you Gut & Green!
Previnex’s new Gut & Green Superfoods powder is my new go-to. It has organic barley and oat grass, alfalfa, spirulina, chlorella, kale and broccoli… and that’s it. Their ingredients are backed by clinical data and contain three specific gut fibers that help promote GI health, digestion, reduced inflammation, and a better microbiome.
With twice of the fiber of my last greens mix and a better flavor, it’s a no brainer for me.
Try it for yourself here at previnex.com and be sure to use code “JASONGREENS” to save 15% off your first order. Don’t tell anyone, but if you put Gut & Green Superfoods powder in your cart, then the 15% off discount will work for anything else you add into your cart as well. Thanks Gut & Green!