DrMirkin's eZine: Strength training to prevent heart attacks

 This is an article from Dr Mirkin's newsletter that I subscribe to.  It is well worth a read, and is very motivating.  It is a not-for-profit endeavour.  He gives permission to share his newsletter, so here it is in the blog.  You could subscribe, yourself.

Dr. Gabe Mirkin's Fitness and Health e-Zine
October 1, 2023

Strength Training May Be More Effective than Aerobic Training to Help Prevent Heart Attacks

Several recent studies show that resistance training for strength may be more effective than aerobic exercise, such as jogging or walking, to help prevent high blood pressure and heart attacks. This may surprise you because many champion body builders and weight lifters have died at very young ages from heart attacks, but the causes of these deaths are likely to have been their use of hormones such as anabolic steroids, growth hormones and insulin.

In one of the new studies, 186 normal-weight and small-muscled type II diabetics were separated into into three groups (Diabetologia, 2023 Oct 01;66(10)1897-1907):
• 63 doing strength training
• 58 doing aerobic training
• 65 doing both strength and aerobic training
Participants were 53-66 years old, with 60 percent men and 40 percent women. HBA1c is a measure of cell damage from high blood sugar levels, and at the start of the study, their mean HBA1c was 13.1, which showed that their diabetes was way out-of-control (normal value is below 5.9).

After nine months, HBA1c values had dropped only in the strength training group and not in the aerobic or combined training groups. Muscle size (appendicular lean mass) increased only in the strength training group.

Other Studies Showing Benefits of Strength Training for the Heart
• A study of almost 30,000 older women followed for 12 years showed that those who did strength training had fewer deaths from heart attacks and all causes than those who did not lift weights (J Am Heart Assoc, Oct 31, 2017;6(11)).
• A study that followed 80,306 adults for two years showed that doing strength training at least twice a week reduced risk for dying from cancers and from all causes by 20 percent (Am J Epidemiol, Dec 12, 2017).
• A review of 14 studies on 253 participants with high blood pressure found that lifting 60 percent of one-repetition maximum at least twice a week for at least eight weeks significantly lowered high blood pressure (Scientific Reports, Jan 5, 2023;13(201).
• Men over 60 who did 12 weeks of resistance training involving bending and straightening the knees against resistance, three sets of 10 repetitions a day, two days a week, increased their ability to move heavy weights by 16 percent. They also had higher blood levels of nitric oxide, which relaxes and opens arteries to increase blood flow to the heart and helps to prevent heart attacks (Br J Sports Med, 2006 Oct; 40(10):867-9).
• A study of 10,500 men who weight trained for 20 minutes a day showed that they gained far less belly fat over 12 years than their aerobic-exercising but non-weight lifting peers (Obesity, Feb 2015;23(2):461-467).
• A review of 13 placebo-controlled studies of the effect of lifting weights in later life on health showed reduced HBA1c, body fat and systolic blood pressure (Sports Medicine, May 2010;40(5):397-415).
• In ten subjects tested after both intense resistance training and aerobic activity, there was increased blood flow to the heart and reduced blood pressure immediately after lifting heavy weights (J Strength & Conditioning Research, October 2010;24(10):2846-52).
• Strength training reduced heart attack risk factors in 28 men who had already had heart attacks (Proc Bayl Univ Med Cent, Jul 2006;19(3):246-248).

Why Most People Should Do Strength Training
You can expect to lose muscle size and strength as you age. Between ages 40 and 50, you lose more than eight percent of your muscle size. This loss increases to 15 percent per decade after age 75. The people who lose the most muscle usually are the least active, exercise the least and are the ones who die earliest. Older people who lose the most muscle are four times more likely be disabled, have difficulty walking, and need walkers and other mechanical devices to help them walk (Am J Epidemiol, 1998; 147(8):755-763). See How Fast Do You Lose Fitness When You Stop Exercising?

My Recommendations
First check with your doctor to make sure you do not have any conditions that will be harmed by exercise. Lifting weights can harm some people by dislodging clots or bursting blood vessels. It can also dislodge plaques to cause a heart attack. Realize that lifting lighter weights with more repetition will enlarge a muscle as much as lifting heavier weights with fewer repetitions, as long as you get Z-line muscle fiber damage characterized by Delayed Onset Muscle Soreness (DOMS).

Join a gym and ask for instructions on how to use the weight-training machines, or hire a personal trainer for a few sessions to develop an at-home resistance exercise program. If you are middle-aged or older and want to start a weightlifting program to gain the health benefits of being stronger and having larger muscles, and at the same time, avoid the extremely high rate of injury in older weight lifters, you should not lift heavy weights when your muscles feel sore and are still damaged from your previous workout. See Keep Your Muscles Strong As You Age and Strength Training Guidelines