🚴VO2max Optimization Protocol

A protocol to optimize cardiorespiratory fitness (as measured by VO2max).

Last updated: May 15, 2024

Conflicts to declare: None.

Please remember to consult with a healthcare provider prior to undertaking any of the protocols available here.

SUMMARY POINTS

What is VO2max and why is it so important?

• VO2max is a measure of maximal oxygen uptake during exercise, which is in turn a measure of cardiorespiratory fitness and is strongly associated with human longevity. In addition to directly improving physical performance by increasing your fitness level, the aerobic exercise required to optimize VO2max also improves your brain health, and by extension, your cognitive performance as well.

• VO2max training can be done via walking, running, cycling, rowing, using an elliptical machine, or any other similarly-paced modality of aerobic exercise.

What is Zone 2 training and how can it help me to increase my VO2max?

• Zone 2 training consists of aerobic exercise where you train well under your lactate threshold (the level above which lactate is produced faster than it can be cleared). In Zone 2, your primary source of energy is fat metabolism. At this level of exertion, your body is not building up lactic acid and hydrogen ions.

• The intensity of exercise required to get you into Zone 2 varies depending on your fitness level. For some individuals, a brisk walk might get them into Zone 2; for those in better condition, Zone 2 means walking uphill or a light jog.

• There are multiple valid strategies for optimizing VO2 max. This protocol reflects the increasingly recommended practice of combining longer duration Zone 2 training sessions with shorter duration High-Intensity Interval Training (HIIT) sessions.

How can I know if I'm training in Zone 2?

The most accurate way to know if you're in Zone 2 is to measure your lactate level in your blood using a lactate meter. For most people, this is impractical because it requires a pinprick blood testing device which costs hundreds of dollars.

Note that your target HR for Zone 2 will shift up and down depending on your fitness level, with more fit people having a higher target HR. Without relying on a lactate meter, you can approximate a Zone 2 heart rate (HR) with the following tools:

• The Talk Test: In Zone 2, you can carry out a conversation but it’s not as comfortable as a regular discussion - i.e., you should be a little more strained. If you can’t maintain a conversation, then that’s too high intensity and you are out of Zone. If you were to have a phone conversation in this state, the person on the other end of your conversation should be able to know that you are exercising based on the way you sound.

• Dedicated Smartphone Apps: You can also use dedicated apps (like Morpheus) that combine wearable-data to calculate your approximate Zone 2 by extrapolating from heart-rate variability.

• By way of crude HR measurement (try to line-up these approximate HR targets with the "Talk Test"):

  • Approximation method 1: Zone 2 target HR = 180 - (your age). If you're fitter than average, add 5-10 bpm to that figure. Use this if you don't know your measured maximum heart rate.

  • Approximation method 2: Zone 2 target HR = 70 - 85% of your known, measured maximum heart rate, depending on your fitness level.

Can I rely on Zone 2 training alone to reliably increase my VO2max or do I need to combine this with higher-intensity training for a better result?

• No—it is more effective to supplement Zone 2 training with HIIT sessions. While Zone 2 training has various health benefits (e.g. improving mitochondrial health), up to 40% of individuals will not respond to lower-intensity Zone 2 training.

• It is therefore necessary to combine Zone 2 training with High-Intensity Interval Training to produce a greater increase in VO2max relative to Zone 2 alone.

What is High-Intensity Interval Training (HIIT) and how can I train in this zone?

• High-Intensity Interval Training (HIIT) consists of alternating between time intervals of higher-intensity and lower-intensity training. Consider the following 32 minute example workout:

  • High-intensity interval: A 4 minute-interval with the highest intensity pace you can sustain for the entire 4 minutes (i.e. not "all-out").

  • Low-intensity interval: Follow the high-intensity interval with a 4 minute-interval at a low-intensity pace such that your heart rate can recover to less than 100 beats per minute.

  • Repeat the cycle above three more times for a total of four cycles.

• For a video overview of different possible HIIT workouts, Rhonda Patrick has a good summary here.

What is your recommended weekly protocol for VO2max optimization?

• Our recommended protocl is taken from Dr. Peter Attia's book on human longevity, Outlive. Note that this requires 3.5 hours of weekly training, in addition to time spent strength training every week as well.

• ATTIA'S PROTOCOL: A weekly training schedule with an ~80:20 | Zone 2:HIIT ratio.

  • 3 hours (or more) of Zone 2 training per week split into 2 90 minute sessions OR 3 one-hour sessions OR 4 forty-five minute sessions.

  • ~30 minutes (or more) of HIIT training consisting of 4 minutes of the highest-intensity pace you can.

  • Maintain an ~80:20 ratio of training time in each of these 2 training modalities.

  • A video summary of this protocol is available here.

  • Note that you can also do your HIIT session immediately after a Zone 2 training session for increased scheduling efficiency.

  • Be mindful that increasing your weekly duration of HIIT training will tax your body more than increasing your weekly duration of Zone 2 training due to its higher intensity, and may require more rest and recovery to avoid overtraining.

I don't have 3.5 hours to train just cardio every week as required by your recommended weekly protocol. Is there a more time efficient way for me to train?

• Yes.

• Individuals who are more time-restricted in their weekly training schedule may focus on only using HIIT training sessions alone, which may produce similar improvements in VO2max with significantly less total exercise time required, albeit without some of the unique benefits and advantages of Zone 2 exercise, such as boosting mitochondrial health and metabolic flexibility. The following session takes ~1.5 hours a week.

• TIME-RESTRICTED PROTOCOL:

• Three weekly sessions of the Norwegian Protocol (discussed at ~7:38 here):

  • A 4 minute interval at the highest-intensity pace you can sustain through the entire four minutes.

  • Followed by a 3 minute lower-intensity interval at a much lower pace where you can recover and where your HR can come down significantly.

  • Repeat the cycle above three more times for a total of four cycles.

How can I measure my VO2max?

1. The most reliable measurement is in an exercise laboratory. We are currently working on a partnership to

2. Some wearable health devices, like the Apple Watch, can also approximately estimate your VO2max.

3. There are also numerous simple manual exercise tests that can approximate your VO2max, such as the Cooper Test. An easier test to complete is the 3-minute step test.

What kind of VO2max do I want to aim for?

• A 2018 study in JAMA indicated that increased cardiorespiratory fitness was inversely associated with mortality with no observed upper limit.

• While it is going to be challenging for most people to achieve an elite level of cardiorespiratory fitness, achieving the 75th percentile for your age group (see table 2 here)- is a more realistically achievable goal for many with consistent training. Alternatively, you can also use this calculator.

• Note that even going from a low to an average VO2 produces a substantial improvement in longevity, and there are decreasing marginal returns to improving VO2max the fitter you are.

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Potential Biomarker Impact of Protocol

Biomarkers this protocol can improve:

• Hemoglobin A1c

• Fasting insulin level

• Fasting glucose level

Non-biomarker metrics this protocol can improve:

• Increased VO2 max

• Decreased Blood Pressure

• Improves Cognitive Performance

Disclaimer: The information provided on this page is for general informational purposes only and does not constitute the practice of medicine, nursing or other professional health care services, including the giving of medical advice, and no healthcare-provider/patient relationship is formed. The content of this article is not intended to be a substitute for professional medical advice, diagnosis, or treatment and the use of this information is provided. Prior to taking any action based on the information on this page, you should speak to your licensed healthcare provider. Our licensed PHC-Nurse Practitioner coaches can assist you with individualized implementation of this protocol and others.