The author presents data supporting the theory that the human body, and the heart in particular, has a built-in system limiting how much activity strain it can endure over time; thereby sounding an alert and preventing heart attack and death. Supporting data includes: heart functions as an independent control system, warm-up before activity, activity strain over time, normal heart rate reduced by strenuous activity, Whoop measures two types of strain: cardiovascular load and muscular load, sudden cardiac arrest and preventive Automated External Defibrillators [AEDs]. The heart is programmed to prevent excessive activity strain.

1. The heart has its own independent brain, placing a limit on how much activity strain it can endure over time.

The human body has three master or independent functioning brains, the head brain, the large intestine or colon and the heart. The heart functions as a separate control to that of the brain. Joe Mechlinski points out that "Your heart can interact independently with the environment to speed up or slow down the heart beat as needed; adjusting the body for survival. ¹

This can vary with age and the fitness level of a person. For example, you can do 5 pushups in one minute or less; 10 pushups in one minute; or 15 pushups in one minute. A physically fit person can do 15 push ups in one minute and feel slight breathing. But a very poor fit person will begin to breath heavily with doing just 5 repetitions. What this means is that the heart has an automatic limit to how much activity strain stress it can endure over time. This is true for all activities we do during the day. Yes, even mental-emotional stress has its limits in causing heavy breathing and possible fainting as warning alerts that one needs to slow down and rest immediately ..... to avoid a heart attack.

2. Warm-up before a game also adds support to the theory.

Most of us are aware of the need to do warm up exercises to get the heart and body prepared for more strenuous game activity. Usually, the warm ups consist of short sprints, stretching, flexibility and strength callisthenic exercises that may last for about 15 minutes. The idea of a workout is to prepare the heart and body for more strenuous activity and prevent a heart attack or sudden death. Warm-up defers provoking symptoms of a heart attack.

3. Although 90% of most heart attacks are caused by ingesting animal fat over a long time, the other 10% of heart attacks are caused by strenuous activity beyond what the heart can endure over time.

The point being made is that heart attacks are caused by exceeding the activity strain load of the heart over time.

Having a special body injury, disorder or disease can add additional strain on an already ailing heart. The extent of the strain depends on several factors, including the severity of the injury or disease, the overall health of the individual, and specific circumstances. Injuries, disorders and diseases lead to an increased demand for oxygen in the body to support healing and recovery processes. This can put extra stress on the heart, as it needs to pump more blood to deliver oxygen to the affected tissues.

4. Normal heart rate reduced by strenuous activity. Avoiding a heart attack involves reducing the strain on your heart and maintaining good heart health. The table below provides the age for a Maximum heart rate that diminishes with age, as displayed in the third column expected strenuous target heart rate: ²

This chart illustrates the maximum heart rate and the expected maximum heart rate of 85% for different ages. For example, at age 80, you could have symptoms [ heavy breathing, feeling faint, chest pain ] of a pending heart attack if your heart rate is 119. Another example, having a disorder lupus probably adds an additional strain of 15% to the target heart rate before heart strain symptoms appear. Thus a 40 year old lupus person would have a target heart rate of 153 - 15 = 138 %. The strain load on the heart of a 40 year old lupus person would illicit protective heart attack symptoms like fatigue and deep breathing; that may not be recognized.

Retirees 80 years and over playing tennis for a length of two hours without rest periods are prime subjects for a heart attack.

5. A commercial approach to evaluating the strain put on your heart and body during the day is WHOOP. Strain measured is a summarizing total of the activity load your body takes on throughout the day. Whoop measures two types of strain: cardiovascular load and muscular load. Cardiovascular being your heart rate, and the higher your Heart Rate [HR] gets and the longer it stays elevated, the more strain you accumulate. The average daily strain for WHOOP members is about 11.0. It decreases with age. When it comes to individual workouts, more intense aerobic exercise leads to higher strain compared to less intense activity. The average strain for 1 hour of running is roughly 12.0, while an hour of walking is about 6.5. The average strain for 1 hour of functional fitness is 10.1. These loads logarithmically combine to create your Day Strain which is scored below in the table below on a scale from 0 to 21: ³

Light Strain (0-9)- This strain category indicates room for active recovery with minimal stress being put on the body.
Moderate Strain (10-13)- This category indicates moderate stress is being put on the body, which helps maintain fitness.
High Strain (14-17)- This category indicates increased stress and/or activity which helps build fitness gains in your training.
All Out (18-21)- This category indicates all-out training or a packed activity day that put significant stress on the body and may be difficult to recover from the day after.

Note: the longer your heart spends at an elevated rate, the higher your strain will be.

You could wake up with a strain score anywhere from 0 - 4; this is perfectly normal.

Your strain score is strictly based on your heart rate data and the amount of time spent in each heart rate zone.

Note: Strain is personalized and accounts for differences in fitness and ability. For example, two people who complete in the same run (distance and level) could get very different strain scores based on those differences (and relative difficulty). An Activity's Strain is a measure of how hard your body worked, and not what your body did. Depending on your fitness level, a very hard workout for you may be a near maximal workout for someone else.

6. Additional data adding support to the proposed theory is sudden cardiac arrest, which is high strain. Some persons are born with this problem. Recently there have been reports of basketball and football players having a sudden cardiac arrest: Hank Gathers 1989, Reggie Lewis 1993; Marc Vivien Foe, Miklos Feher, Antonio Ouerta 2004-2007; "Pistol" Pete Maravich 1988; and long distance runner Jim Foxx 1984. ⁴

Most of these deaths could have been prevented if Automated External Defibrillators [AEDs] had been available to the coaches and training staff. The odds that any person or given athlete will die suddenly are very small. Estimates range from 1 in 50,000 to 1 in 80,000 a year among high school and college athletes.⁵

The heart is programmed to prevent excessive activity strain.

When? Shortness of breath can occur when a person is physically unfit and trying to exercise or do heavy activity.

How? You will experience shortness of breath. This symptom can occur before chest discomfort.

Experiencing deep breathing can lead to dizziness or light-headedness, and even fainting.

Experiencing these symptoms of shortness of breath, dizziness or fainting does not mean that you just suffered a heart attack. It is your heart and brain warning you to slow down and rest. This alert is overlooked by most doctors and people.

Prevention:

Today, 2023, there is concern about many persons of all ages having mental health issues and breakdowns. Emotional stress over extended time can put a strain on the heart. But there the excellent video below lists foods that can prevent a heart attack:

7 foods that unclog arteries and naturally prevent heart attack Length = 9:03 mns.

DailyHealthPost Source:

Summary:

The author presented data supporting the theory that the human body, and the heart in particular, has a built-in system limiting how much activity strain it can endure over time. Supporting data includes: heart functions as an independent control system, warm-up before activity, activity strain over time, normal heart rate reduced by strenuous activity, Whoop measures two types of strain, that of cardiovascular load and muscular load, and sudden cardiac arrest with preventive Automated External Defibrillators [AEDs].

The heart is programmed to prevent excessive heart strain by issuing alert symptoms.

We need to be aware that sudden vigorous activity puts a strain on the heart. And pay attention to symptoms of feeling fatigue, deep breathing and shortness of breath; take time out to rest.

References:

1 Mechlinski Joe, "Understanding The Three “Brains” in Our Body (And Their Critical Role at Work)," Neuroscience, Sep 5, 2018.   Mechlinski: Three body brains 2018

2 Nall Rachel, "Your Guide to Stress Test Results by Age, HealthLine, March 9, 2023.  Hall: Guide stress test by age 2023

3 Whoop Strain, Jun 30, 2023.  Whoop strain 2023

4 Bickel Trenton, Prasad Gunasekaran, Ghulam Murtaza, Rakesh Gopinathannair, Sampath Gunda, and Dhanunjaya Lakkireddy, "Sudden Cardiac Death in Famous Athletes, Lessons Learned, Heterogeneity in Expert Recommendations and Pitfalls of Contemporary Screening Strategies," Journal of Atrial Fibrillation, December 12, 2019.  Bichel: Dealth of famous athletes 2019

5 Fogoros Richard N., “Sudden Death in Young Athletes,” VeryWell Health, November 01, 2022.  Fogoros: Sudden death in athletes 2022

6 Parades, "Eric Parades Save a Life Foundation," 2009.  Parades: Life Foundation 2009

Masters Maria, "8 Causes of Chest Pain That Aren't a Heart Attack," Health, October 10, 2023.  Masters