Zone 2 vs MAF Training: What's the Difference and Which Is Right for You?

Low-intensity training has never been more discussed. Between Peter Attia's deep dives into Zone 2 on his podcast and the growing number of endurance athletes rediscovering Dr. Phil Maffetone's MAF method, "train slower" has become the most counterintuitive performance advice that actually works.

But Zone 2 and MAF training are not the same thing. They share a philosophy and a lot of overlap, but the mechanics differ in ways that matter depending on who you are and what you're trying to build. Here's a clear breakdown.

What Is Zone 2 Training?

Zone 2 is defined as a percentage of maximum heart rate, typically 60-70% of HRmax. It corresponds to a metabolic state where lactate production is low and the aerobic system is doing the primary work.

Peter Attia, one of the most prominent advocates of Zone 2 training, describes it as the highest intensity at which lactate remains below approximately 2 mmol/L. At this level, the mitochondria in slow-twitch muscle fibers are being maximally stressed without producing significant lactate accumulation. Over time, that stress drives mitochondrial density and fat oxidation improvements.

In practice, Zone 2 training looks like a conversation-pace run, a moderate cycling effort, or any sustained aerobic work where you're breathing comfortably but not casually. The talk test often used: you can speak full sentences, but you wouldn't want to recite a monologue.

Zone 2 is framework-agnostic. It's used by cyclists following the Coggan power zones, runners using Garmin or Polar heart rate zones, and high-performance athletes whose coaches structure training around lactate threshold testing.

What Is MAF Training?

MAF training is built around Dr. Phil Maffetone's 180 Formula, a method for calculating an individualized aerobic ceiling called the MAF heart rate.

The formula: 180 minus your age, then adjusted based on health and training history:

• Subtract 10 for significant illness, injury, or overtraining
• Subtract 5 for inconsistent training history or less than two years of consistent training
• No adjustment for healthy, consistent training of two or more years
• Add 5 for two or more years of consistent training with steady progress

The result is your maximum aerobic heart rate. All base-building training happens at or below this number. Dr. Phil Maffetone developed this approach through clinical work with athletes across decades, and the central idea is the same as Zone 2: keep intensity low enough that the aerobic system develops rather than gets depleted.

The key difference is in how the ceiling gets set.

Zone 2 vs MAF: Key Differences

| | Zone 2 | MAF (Maffetone) | |---|---|---| | How the zone is set | Percentage of max HR (60-70%) | Formula: 180 minus age, with adjustments | | Individualization | Limited — depends on accurate max HR | High — accounts for health and training history | | Requires lab testing | Sometimes (lactate) / sometimes not | No — formula-based | | Accounts for overtraining | No | Yes — subtract 10 for overtrained state | | Accounts for injury history | No | Yes — subtract 5 or 10 for recent injury | | Training history factor | No | Yes — add or subtract based on consistency | | Developed by | Multiple researchers / coaches | Dr. Phil Maffetone | | Primary proponents | Peter Attia, Stephen Seiler | Dr. Phil Maffetone, Mark Allen |

Where They Overlap

Both approaches share the same underlying goal: develop the aerobic base by training at intensities that stress the aerobic system without generating significant metabolic fatigue.

Fat adaptation. Both Zone 2 and MAF training are primarily fat-burning zones. Training here repeatedly improves the body's ability to oxidize fat at higher intensities, which delays glycogen depletion and increases endurance capacity.

Aerobic base volume. Both frameworks call for high volumes of low-intensity work as the foundation of training, not as filler between hard sessions but as the primary driver of adaptation.

Mitochondrial development. The adaptations both approaches target are the same: mitochondrial density, capillary development, oxidative enzyme activity. The mechanism is identical even if the methods for finding the right ceiling differ.

Injury reduction. By keeping the bulk of training at low intensity, both approaches reduce cumulative physiological stress and injury risk compared to moderate-to-high intensity training.

For many athletes, the Zone 2 range and the MAF heart rate will land close to each other, or even overlap entirely. But for many others, they diverge significantly.

Where They Diverge

Precision for non-standard athletes

Zone 2 based on 60-70% of max HR assumes a relatively standard physiological profile. For a 30-year-old with a max HR of 195, Zone 2 is roughly 117-137 bpm. That's a wide range, and the upper end may push some athletes into anaerobic territory while being too conservative for others.

Dr. Phil Maffetone's 180 Formula produces a single number rather than a percentage band, and it adjusts for factors that generic zone calculations ignore: your actual health status, recent illness, injury history, and training background.

The overtraining blind spot

Zone 2 calculated from max HR has no mechanism to account for an overtrained or depleted physiological state. An athlete who has been training too hard for too long may have a suppressed aerobic system that needs to operate at lower intensities than a percentage-based formula would suggest.

The 180 Formula addresses this directly. The subtract 10 adjustment for athletes in an overtrained state is one of the more clinically grounded features of Dr. Phil Maffetone's method. It acknowledges that "where you should train" is not just about your age and max HR, but about your current physiological capacity.

Injury and recovery context

Zone 2 doesn't change based on whether you've been injured. MAF does. A runner returning from a stress fracture gets a lower MAF ceiling than a healthy version of the same person. That lower ceiling reduces structural load and hormonal stress during a vulnerable period. It's the kind of nuance that makes Dr. Phil Maffetone's approach more conservative and often more appropriate for injury-prone athletes.

How zones are established

To set Zone 2 properly, you need an accurate max HR. The common 220 minus age formula is notoriously imprecise, with real-world variation of plus or minus 10-20 bpm. That error propagates into your zone calculation. A lab-based lactate test removes the guesswork, but most recreational athletes never get one.

The MAF 180 Formula doesn't require max HR at all. It's self-contained and based on inputs any athlete can assess themselves.

Who Zone 2 Works Best For

Zone 2 is a strong choice if:

• You train with a power meter (especially cyclists) where watt-based zones are more reliable than HR zones
• You have access to lactate testing and want physiologically precise zones
• You're working with a coach who structures periodization around zone models
• Your training history is consistent and your health is stable, so generic percentage zones are reasonably accurate

Zone 2 is also better established in the elite cycling and triathlon literature, so if you're working within those communities and norms, the language and framework are already understood by the people around you.

Who MAF Works Best For

Dr. Phil Maffetone's MAF method tends to be a better fit if:

• You have a history of injuries or overuse problems
• You've been training hard without clear progress (classic overtraining sign)
• You've had inconsistent training due to illness, life, or injury
• You're coming back after a significant layoff
• You're new to structured training and want a clear, non-technical ceiling
• You want a single number to aim for rather than a zone band

MAF is also practical in a way that lactate-based Zone 2 isn't. No lab, no complicated testing protocol. Calculate the number, strap on a heart rate monitor, and keep your effort below the ceiling. The simplicity is a feature.

Common Zone 2 Misconceptions

"My watch Zone 2 is Zone 2." Garmin, Apple, and Polar use default max HR formulas that are often wrong for individual athletes. Your watch Zone 2 may be meaningfully different from your actual aerobic threshold. Dr. Phil Maffetone's formula, because it doesn't rely on max HR, sidesteps this problem entirely.

"I can train at the top of Zone 2 most of the time." Regularly training at the top of any low-intensity zone creates chronic moderate stress. Both Peter Attia and Dr. Phil Maffetone emphasize that most athletes train too hard in their easy sessions. The 80/20 rule (80% easy, 20% hard) often becomes 60/40 or worse in practice.

"Zone 2 is the same for everyone at the same fitness level." It isn't. Two athletes of identical age, weight, and VO2max can have different aerobic thresholds based on training history, stress levels, and health status. Zone 2 calculated from a percentage doesn't know that. The MAF adjustment factors do.

Can You Combine Zone 2 and MAF?

Yes, and many athletes effectively do. If your Zone 2 range and your MAF heart rate land in a similar place, you're already training in the combined sweet spot. The frameworks are compatible.

If they diverge, the practical recommendation is to use whichever ceiling is lower during base-building phases, especially if you have any history of injury, overtraining, or inconsistent health. Being conservative in the early phases of aerobic development costs nothing and reduces risk.

Q&A

Is MAF the same as Zone 2?

No, but they target similar physiology. Both Zone 2 and Dr. Phil Maffetone's MAF training aim to develop the aerobic system by keeping training below the aerobic threshold. The difference is in methodology: Zone 2 is set as a percentage of maximum heart rate (typically 60-70%), while MAF uses the 180 Formula to produce an individualized ceiling based on age, health status, and training history. For some athletes the numbers will be close. For others, particularly those with injury history or inconsistent training backgrounds, MAF will produce a notably different and often lower ceiling.

Which is better for fat burning?

Both approaches train fat oxidation, which is the primary adaptation from sustained low-intensity aerobic work. The key is staying below the aerobic threshold. In practice, Dr. Phil Maffetone's MAF method may produce better fat-burning outcomes for athletes who have been unknowingly training above their aerobic threshold, because the formula accounts for individual variation that generic Zone 2 percentages miss. An overtrained athlete using a percentage-based Zone 2 may still be training too hard. The MAF adjustment factors would catch that and lower the ceiling accordingly.

Can I combine Zone 2 and MAF training?

Yes. Many athletes use both frameworks or find that they produce similar numbers. If your calculated Zone 2 range and your MAF heart rate overlap, you're training in the same aerobic zone regardless of which label you use. If they diverge, consider using the more conservative number during base-building phases, particularly if you're building from scratch, returning from injury, or have a history of overtraining. Peter Attia's Zone 2 emphasis and Dr. Phil Maffetone's MAF method are both pointing toward the same underlying physiology. The frameworks are complementary, not competing.