Aerobic Base Training: The Praise of Slowness

If you’re not suffering, you’re not progressing. No pain, no gain. But what if we told you otherwise? What if we told you that running slowly, without feeling like you’re about to die with each step, is just as important as pushing yourself to the limit? Here’s everything you need to know about this often overlooked slow pace.

Common misconceptions die hard, much like your feet hardened from miles of training. Among these is the widespread belief that a slow-paced run is pointless. Not pushing yourself and not suffering is like running in vain. But why do the greatest champions often train with complete ease, enjoying the breeze with smiles on their faces? Simply because they understand that to run better, longer, and faster, a significant portion of training should be done at a slow pace. In running jargon, these easy paces are called “aerobic base training.”

What exactly is aerobic base training?

In simple terms, it’s a jog performed with complete respiratory and muscular ease. Practically speaking, it’s when you’re able to talk while running without gasping for air every 30 seconds. It feels like you could run at this pace for hours without getting tired by the end of the session.

More specifically, aerobic base training (ABT) corresponds to the heart rate (HR) range between 60 and 75% of your maximum HR, and lactic acid should remain below 2 mmol/liter of blood. Okay, the likelihood of you pricking your finger to analyze your blood droplet is low! While most runners now own a heart rate monitor (if you don’t yet, it’s time to gear up at a low cost), not everyone knows their max HR. The best indicator is probably the total ease we mentioned earlier.

Caution! It’s easy to slip into active endurance, in other words, to jog a bit too quickly! You might feel like you’re running easily when, in fact, the pace is slightly too high. This is less noticeable when training alone since you can’t test the easy conversation during effort. A tip: if you don’t have a running buddy, take your earbuds and make a phone call during your run.

Why is running slowly beneficial?

➡️ Reason #1: Real Physiological Benefits

At aerobic base training intensity, the lactate level (lactic acid produced by muscles, red blood cells, and skin when the body lacks oxygen) remains stable and relatively low: muscles and blood don’t become overly acidic as the amount of lactic acid produced is low enough to be easily eliminated.

When intensity is low (around 60% of max HR) and the first several minutes have passed, the energy pathway shifts: we move from the carbohydrate pathway, where carbohydrates are used as fuel, to the fat-burning pathway, where reserve fats are burned. The more you practice aerobic base training runs, the more your body becomes capable of breaking down fats early and intensively. This is quite interesting if you want to lose body fat and be more competitive on long distances!

At a slightly higher intensity (around 75% of max HR), other qualities are developed: muscular oxygenation and cardiac contractile qualities are improved. This enhances muscular capillarization and cardiovascular endurance, but also heart filling and resistance to effort. Better supplied with blood and oxygen, muscles can produce more energy and perform better.

➡️ Reason #2: Improved Running Economy

Aerobic base training runs improve muscle resistance and tendon elasticity. They provide an opportunity to work on running economy, meaning adopting a running cadence that consumes less energy, refining foot placement, and general posture. Being mindful of running technique during these easy sessions helps you develop habits that will be beneficial at faster paces.

Focusing on running technique also allows you to be more present in the moment and disconnect from daily worries. You concentrate on your sensations and perceptions: your body’s position in space, arm position, breathing rhythm, air slipping over your face, the sounds around you… Running becomes an excellent way to combat stress and, subtly, practice mindfulness!

In practice, what does it look like?

👉 If you’re a beginner or returning from an injury or break:

The vast majority of your training should be aerobic base training. The goal is to run longer and longer without going faster to give your body time to adapt to the biomechanical and physiological demands of running. An occasional short interval session like 30/30 (30 seconds fast followed by 30 seconds recovery) can be scheduled, but only after several weeks of gradual progression.

👉 If you run regularly (2 to 3 times a week):

Two-thirds of your training should be aerobic base training. The remaining third corresponds to higher intensities. If you run three times a week, plan two aerobic base sessions and one interval session.

👉 If you’ve been running for years and very regularly:

Aerobic base training must be an integral part of your training! You should practice it consistently: during warm-ups before intense sessions, during cool-downs after intervals, during recovery jogs between tough sessions, or during long runs. The “75% of training volume should be ABT” rule still applies to you.

• Marathon Calendar in France, here.