MAF Training Glossary
Key terms and concepts you'll encounter in MAF (Maximum Aerobic Function) training, explained in plain language.
180 Formula (Maffetone Method)
The 180 Formula is a simple method developed by Dr. Phil Maffetone to calculate your maximum aerobic heart rate. Subtract your age from 180, then adjust based on health and fitness history. This number becomes the ceiling for your aerobic training.
Aerobic Base
Your aerobic base is the foundation of endurance fitness built through consistent low-intensity training. A strong aerobic base allows your body to efficiently use fat as fuel and supports faster recovery. Building this base is the primary goal of MAF training.
Aerobic Deficiency Syndrome (ADS)
Aerobic Deficiency Syndrome occurs when an athlete's aerobic system is underdeveloped relative to their anaerobic system, often from too much high-intensity training. Symptoms include slow recovery, frequent injuries, and plateauing performance. MAF training directly addresses ADS by rebuilding the aerobic foundation.
Aerobic Threshold
The aerobic threshold is the exercise intensity at which your body begins to supplement fat burning with significant anaerobic energy production. Below this threshold, your body primarily uses fat for fuel. MAF training keeps you at or below this threshold to maximize aerobic development.
Anaerobic Threshold
The anaerobic threshold is the intensity at which lactate accumulates in the blood faster than it can be cleared. Training above this point relies heavily on sugar for fuel and creates more metabolic stress. MAF training intentionally stays well below the anaerobic threshold to build endurance without excessive stress.
Base Building Phase
The base building phase is a training period focused exclusively on aerobic development, typically lasting three to six months. During this phase, all workouts stay at or below the MAF heart rate with no high-intensity sessions. This patient approach builds a durable aerobic engine that supports faster training later.
Fat Adaptation
Fat adaptation is the metabolic shift where your body becomes more efficient at burning fat as its primary fuel source during exercise. This develops over weeks and months of consistent low-intensity training at or below your MAF heart rate. A fat-adapted athlete can sustain longer efforts with more stable energy levels.
Heart Rate Variability (HRV)
Heart rate variability measures the variation in time between consecutive heartbeats and is a key indicator of autonomic nervous system health. Higher HRV generally indicates better recovery and fitness. Consistent MAF training often improves HRV over time as the aerobic system strengthens.
Heart Rate Zone
A heart rate zone is a defined range of heartbeats per minute used to target specific training intensities. Traditional models use five zones from easy to maximum effort. MAF training simplifies this by focusing on a single zone at or below your MAF heart rate for aerobic development.
Low Heart Rate Training
Low heart rate training is an approach that caps exercise intensity at a specific heart rate to keep effort in the aerobic zone. It requires slowing down significantly, especially in the early stages, which many athletes find challenging. Over time, pace improves at the same low heart rate, demonstrating aerobic progress.
MAF Heart Rate
Your MAF heart rate is the maximum heart rate for aerobic training, calculated using the 180 Formula. Training at or below this rate ensures you stay in the aerobic zone where fat is the primary fuel source. It serves as the foundation of the Maffetone Method for building endurance.
MAF Score
The MAF Score is a metric that tracks what percentage of your workout time is spent within the MAF heart rate zone. A higher score indicates better aerobic discipline and training compliance. AerobAce calculates this automatically from your Strava activities to help you monitor consistency.
MAF Test
The MAF Test is a standardized assessment where you run or walk at your MAF heart rate and record your pace over a fixed distance. Repeating this test monthly reveals whether your aerobic fitness is improving, stagnating, or declining. It is the primary benchmark for tracking MAF training progress.
Maximum Aerobic Function
Maximum Aerobic Function refers to the highest level of aerobic output your body can produce while remaining in a fully aerobic state. It represents the point of peak fat-burning efficiency during exercise. The entire MAF training philosophy is built around developing and optimizing this function.
Overtraining Syndrome
Overtraining syndrome is a condition caused by excessive training without adequate recovery, leading to persistent fatigue, declining performance, and increased injury risk. It often results from too much anaerobic training and insufficient aerobic base work. MAF training helps prevent overtraining by emphasizing low-stress aerobic exercise.
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