Most Important Math Equation To Know
We all took math classes in school but in my opinion, I think they missed out on teaching us perhaps one of the most important math equations to know which is the following;
(220 – your age) x 50% to 85%
Before I break down what exactly is the above math equation, let me briefly tell you why I was motivated to write this article. A few weeks ago, one of the members from my scuba dive group emailed me and told me he suffered a heart attack and had to go in for quadruple bypass heart surgery. Fortunately he survived. But heart disease is something that progresses over time and our diver was extremely lucky not to have a heart attack when he was underwater in Cozumel just a few weeks prior to his incident. He as well as our dive group was also lucky that he didn’t have a medical incident when he was in the water with us during the last two seasons while diving in cold water.
It would have been a real setback for our dive group to have to deal with such an incident since the vast majority of fatal dive accidents are caused by either divers running out of air or those having some sort of medical event while in the water — both which are very preventable.
He had been scuba diving for years but stopped for about 30 years until he met me which spurred his interest in diving again. So he bought new scuba gear and dived in local cold waters with my group for the last two years. His Cozumel dive trip was his long awaited return to diving tropical waters again. I’m so glad that he got those two years of diving with us plus his trip to Cozumel which he said was awesome with all the marine life down there. But the reality now is that there’s a good chance that he might not be allowed to ever dive again.
Cardiac patients will need to get medical approval, usually from doctors specializing in dive medicine as well as their cardiologist in order to scuba dive again. Although we do hear that a few former cardiac patients end up running marathons, they are truly the exception as they did complete overhauls in their health and fitness lifestyles. Such drastic changes in their ways are just not reality for most people.
Just this past week, there was news that a younger dive instructor died during a dive out in Kingston, Ontario. It was reported that this diver did have cardiac issues and was recently diagnosed with diabetes. So with these two recent cases happening, this is a real wake up call not only to my dive group but should be to all folks in general.
How The Math Formula Works
So let’s revisit that math formula again;
(220 – your age) x 50% to 85%
The first part (220 – your age) is your maximum heart rate that your own heart is estimated to beat. So if somebody is age 50 for example, his or her maximum heart rate would be 220 – 50 = 170 heart beats per minute.
Now take 170 x 50% to 85% which will be 85 to about 144 beats per minute. This is the heart rate one should be sustaining during cardiovascular exercise. A lower range from 50% to 70% is recommended for those people who want to lose weight. This means that in order to lose weight in the form of body fat, somebody age 50 should be doing continued cardiovascular exercise with a heart rate of 85 to 119 beats per minute.
When many people simply go outside to do casual walks in order to lose weight and wonder why they are not successful in shedding pounds, they are very likely not being active enough to sustain a heart rate of 50% to 70% of their maximum heart rate, ie., they are walking too darn slow! Any activity resulting in lower than 50% of maximum heart rate is virtually useless in losing weight (and of course diet will be also important here as well).
For people training for cardiovascular fitness health rather then just losing weight, it’s recommended to exercise at the higher level from 70% to 85% of maximum heart rate. So for the same 50 year old, this will mean 119 to 144 beats per minute for cardiovascular fitness health. Elite athletes train at over 85% of maximum heart rate.
In any case, best benefits will result from sustained exercise with your target exercise heart rate for at least 30 minutes at a time.
Now back to scuba divers — especially for divers getting older. We should all be doing enough cardiovascular exercise with target heart rates in mind, ie., 50% to 85% of our maximum heart rate for at least 30 minutes a few times per week plus watch our diets. I see a lot of big (overweight) divers out there at many dive sites both locally and abroad. These folks are dive accident time bombs. Remember that a significant number of fatal dive accidents result from medical events in the water.
If any of us are in doubt with our own current health, we should seek medical advice regarding scuba diving. We should be responsible divers not only to ourselves but also to our dive buddies especially since they are the ones who have to deal with you in the water if you have a medical event during a dive.
My Own Health & Fitness Plan To Ensure Diving Safety
I know that for many people including myself, cardiovascular exercise can be boring. But if you want to prevent having a medical incident in the water or on land, it’s a must. For myself, I do a variety of different activities for cardiovascular health making sure that I get my heart rate up to about 70% to 75% of my own maximum heart rate each time.
I’ll do stationary bike in the gym (while listening to music), rollerblade on my street, swim laps in the pool, martial arts forms in my backyard and in the winter I do some fairly high intensity skiing that gets my heart pounding by the time I get to the bottom of a slope. I also watch my diet too avoiding eating junk.
So cardiovascular exercise does not have to be so boring that you quit because of that. Find enough ways like listening to music or podcasts while in the gym and/or do other activities that you like that will increase your heart rate enough to sustain that 50% to 85% of maximum heart rate range (so activities like casual walking and playing golf will not be enough).
For all scuba divers out there, let’s have long safe diving lives. As for all non-divers, the concepts I outlined in this article should apply to you as well for longer and healthier lives.
