The cardiovascular system, which consists of the heart and the lung deserves due training to become adaptable towards all kinds of physical strain. Marathon running being an endurance sport is also “full impact” in nature and hence increases the strain on the cardio vascular system significantly. Hence, to keep the sport risk-free, one needs to indulge in “Heart-rate based training”. The goal of this training is to adapt the heart to various heart rate zones, making it easy on the heart when it is exposed to varying heart rates.
What Heart Rate Monitoring is NOT.
Let me clear the air of myths surrounding the runner's world regarding “Heart Rate Monitoring” . A heart rate monitor is not to monitor whether you are “blowing up” your heart or not. It is made to believe that running beyond a particular heart rate may be counter productive or risky. The body is not governed by knowledge but intelligence. That means it is not directly controlled by us but by our “Autonomic Nervous” system. The autonomic nervous system governs all the internal functioning like metabolism, digestion, assimilation, absorption. There are other factors other than exercise intensity which influences the heart rate too. For example if you take a roller coaster ride or any other amusement rides for the first time, you tend to experience a sudden rise in heart rate. It does not that mean you are exercising harder. Our anxiety levels also reflect in heart rate elevation. That is why on a race day our heart rate is slightly higher than our training heart rate by approximately 10bpm. Do not keep staring at your heart rate monitors to see whether you are going over board or not. If you are going over board all that will happen is you will enter fatigue zone and the body will just force you to drop speed or stop. You will not end up with a cardiac arrest.
What is Heart Rate Based Training?
A heart rate based training is basically to get your heart familiar with sustained heart rates for longer times in different zones. Without proper cardiac conditioning it is very likely that we push harder with an untrained heart and run in a “Fatigue Zone” which makes the body very vulnerable to musculo-skeletal injuries. Let me explain this – only when you run or train to run with sustained heart rate zones will all your muscles and other structures which are involved in running get a steady flow of oxygen and constant removal of metabolic waste products at a cellular level. This enables running and the contrary hampers performance and leads to injuries. This is why many runners get injured in the latter half of any race and not during the first half.
To train in a heart rate based program you need to calculate your target heart rate. The Karvonen formula is the best, in my view.
Target Heart Rate = ((max HR − resting HR) × %Intensity) + resting HR example
.I would not say they are accurate but atleast valid from a reference point of view. Based on this formula one may derive his 60% Max Heart Rate (MHR), 70% MHR, 80% MHR, 90% MHR.
Validity on a practical stand point:
This is the verdict. Once the various percentages are calculated one needs to start sustaining those heart rates for longer durations like gradually from 3km to 40km. Also, when the body enters the fatigue zone you will see the heart rate creeping higher and performance starts dropping. The idea is to train the heart to sustain and not push it in the fatigue zones. Beginners might enter the fatigue zone very soon. But don’t worry. Once you enter the fatigue zone you need to stop or slow down. Do not prioritize distance over fatigue. If you do so you may delay your own cardiac conditioning. Train smart.
To add further more validity to heart rate monitoring you may cross refer the pace. As your ability to sustain a particular heart rate pace increases you should also see that your pace should increase eventually at the same heart rate without any additional increase in heart beats. This does takes a while but shows a different paradigm of endurance achieved. Hence my view is that heart rate conditioning should always be mapped in cross comparison to pace for better training results and higher cardiac endurance.
Have a great training ahead folks.