Heart rate is a fantastic tool for endurance training and when used correctly can help you to make significant gains in your chosen sport.
The Power of the Aerobic Base
“Train don’t strain” Arthur Lydiard
Endurance athletes, new and old, are forever training too hard. Their idea of training has spawned from the “no pain no gain” adage of last century. This applies to juniors through to adults, and unfortunately for these athletes, this type of training produces more harm than good.
Aerobic fibres are sometimes called “red” fibres because they contain structures called mitochondria. Mitochondria use oxygen to convert chemical energy into mechanical energy (movement).
The more you train your aerobic muscles, the more mitochondria develop and the more oxygen is utilised to help generate force and move you forward. The fuel for the mitochondrias’ powerful endurance energy is almost 100% fat.
Sugar (glucose) is converted to mechanical energy in the absence of oxygen by anaerobic muscle fibres. These are sometimes called fast-twitch or white muscle fibres due to their lack of red mitochondria. The high power nature of these muscles means that they are used very little in endurance sports.
Some muscle fibres have a combination of aerobic and anaerobic qualities. These fibres are very important in endurance training and competition. When these fibres are highly developed, they act like powerful aerobic fibres. Developing their aerobic quality further improves endurance and, most importantly, what is call “aerobic speed”, or the ability to go faster with the same or less effort.
Focus on the Aerobic System
The aerobic energy system is the most dominant energy conversion system when it comes to anything over two minutes in duration. A study carried out by the University of Western Australia showed that males and females generate 60–70% of muscular contractile energy from aerobic metabolism for an 800 m run (approx. 2 min) and up to 86–94% for a 3000 m running race (9–11 min). Regardless of your choice of endurance event, the aerobic energy system is the essential system that needs training.
What Most Athletes Do
Rather than building speed through the development of the aerobic and mixed muscle fibres over time, most athletes rely on their anaerobic system to run/ride/swim faster.
These athletes aren’t developing their aerobic system full and as a result, often suffer from various forms of overtraining.
Summary of Aerobic Training Benefits.
- Build more mitochondria
- Use oxygen more efficiently
- Burn more fat
- Preserve carbohydrates (glucose/glycogen)
- Run/ride/swim faster for a longer
Utilising Heart Rate
To train the aerobic system effectively, you must train below your anaerobic threshold. To ensure you’re training at the right intensity, you can use a heart rate monitor.
There are a million and one ways to find your heart rate zones, and I’ve done them all—from lactate testing in the lab to time trials on the track. The method that I found to be the most practical on a day-to-day basis is the 180 formula, which was developed by sports medical professional, Dr Phil Maffetone.
The 180 formula calculates the maximal aerobic training heart rate, and incorporates an athlete’s training age as opposed to their chronological age (years) which can often be dramatically different. Think of a 50-year-old who has been training since age 15 vs. a 50-year-old who is new to training. They would respond very differently if the “220 minus your age” formula was used.
Calculate Your Own Maximum Aerobic Training Heart Rate
There are two important steps to find your maximal aerobic training heart rate,
- Subtract your age from 180.
- Modify this number by selecting one or more of the following categories that best matches your fitness and health profile:
a. If you have or are recovering from a major illness (heart disease, any operation or hospital stay, etc.) or are on any regular medication, subtract an additional 10.
b.If you are injured, have regressed in training or competition, get more than two colds or bouts of flu per year, have allergies or asthma, or if you have been inconsistent or are just getting back into training, subtract an additional 5.
c.If you have been training consistently (at least four times weekly) for up to two years without any of the problems just mentioned, keep the number (180 – your age) the same.
d. If you have been training for more than two years without any of the problems listed above, and have made progress in competition without injury, add 5.
For example, if you are thirty years old and fit into category (b), you get the following:
180 – 30 = 150. Then, 150 – 5 = 145 beats per minute (bpm).
In this example, 145 should be the highest heart rate for the majority of endurance training. This is highly aerobic, allowing you to build an aerobic base most efficiently. Training above this heart rate rapidly incorporates anaerobic function, exemplified by a shift toward burning more sugar and less fat for fuel. Your aerobic threshold value essentially puts a number on Arthur Lydiard’s long slow miles concept.
Setting Your Zones
Once you have your aerobic threshold calculated, you can begin to set your zones.
We’ll use the same example from above with an aerobic threshold of 145 bpm
- Zone 1—recovery/easy: anything below threshold minus 10 bpm (<135 bpm)
- Zone 2—aerobic threshold: from minus 10 bpm up to your threshold (135–145 bpm)
- Zone 3—tempo/marathon–half marathon pace: from your threshold to plus 15 bpm (145–160 bpm)
- Zone 4—hard: anything above threshold plus 15 bpm (>160 bpm)
Initially, training at this relatively low rate may be stressful for many athletes. “I just can’t train that slowly!” is a typical comment. But, after a short time, you will feel better, and your pace will quicken at that same heart rate. You won’t be stuck training at a slow pace for too long. Still, for many athletes, it is difficult to change bad habits! But I recommend giving it one month.
PhD Sport Scientist