When it comes to your health, your blood pressure is one of the most important indicators to your health. Exercise can improve various areas of your health, however exercising incorrectly can also have a negative effect.
When you lift a heavy weight or work your muscles with high intensity your blood pressure increases. If you already have high blood pressure it can lead to the thickening of the left ventricular wall in the heart (known as concentric hypertrophy). The thickening happens because your heart is a muscle and this increase in pressure will make the heart adapt just like any other muscle and it will increase in size. However the thickening of the ventricular wall isn’t good for you. Even worse are those people who hold their breath or try to breath out with a closed mouth when lifting heavy weights or even straining on the toilet. Why? when you do this, you close off your epiglottis and bloke your airways, this will increase your internal pressure by a huge amount and can really ramp up your blood pressure. This process is called the ‘Valsalva manoeuvre‘. Trainers who attempt very heavy lifts can actually suffer from what is referred to as the weightlifters blackout, where they go from very high blood pressure and stop the flow of blood and then there is a huge drop in blood pressure. These situations can all lead to some serious cardiac problems.
The thickening of the wall reduces the internal cavity area and therefore reduces the amount of volume of blood in the heart, which then requires an increase in your heart rate in order to supply more blood.
A healthy blood pressure is normally around 120/80, but when you lift a heavy weight this can increase to over 300/250, especially if you don’t breath properly or you hold your breath.
It’s important to note that much of the badness I’m talking about comes from those with a preposition for high blood pressure, cardiac issues or are overweight and from the holding of breath for longer than 10 seconds during lifting heavy weights. However in healthy individuals it shouldn’t be too much of an issue if you use proper breathing techniques or moderate weights.
Those that have a blood pressure in the normal range, should be OK with the temporary increase in blood pressure from exercise. Just remember to breath properly throughout the exercise and that the heavier the weights lifted, the higher the blood pressure spike increase will be. All things being equal a healthy body should not having any problems lifting heavy weights.
Also to note is that regular moderate intensity exercise done correctly can improve your heart health and blood pressure. Please see the heart article.
Why aerobic activity is great for the heart
Doing aerobic activities stretches the muscle (eccentric hypertrophy), increases the internal cavity and increases the amount of volume the heart can pump. Also aerobic activities helps to build new capillaries and other changes in our blood vessels leading to a better blood flow. This also helps manage our PH levels, makes your heart more efficient and reduces your resting heart rate and blood pressure.
If you are in any doubt, I strongly recommend having a heart screen or your blood pressure monitored before you plan on working out and also on a regular basis thereafter. Anything over 140/90 (hypertension) should be considered high, but even anything over 120/80, should be kept an eye on.
Hypertension (high blood pressure) is a silent killer, it shows no symptoms, but causes damage to the blood vessels, which can lead to various heart problems.
Bottom line, final thoughts and my recommendation
Both lifting weights and aerobic activity cause concentric hypertrophy and eccentric hypertrophy, but one does more than the other, as explained above. The lifting of weights will make your heart thicker and stronger, while the aerobic activity will make it bigger. Lifting weights will only be a problem for those that either lift too heavy and hold their breath for too long and/or people who already have high blood pressure.
If you are an older trainer, obese/overweight, have cardiovascular problems, high blood pressure or smoke take extra care to ensure you monitor your blood pressure and look to improve your diet by reducing salt and sugar and follow a good nutritional plan and follow a progressive workout schedule tailored to your needs.
It may also be helpful to read about high blood pressure here.
