Study: The Weight You Gain When Quitting Smoking May Actually Be Muscle
Here’s a new and better reason to quit smoking, and for good. A year-long study led by researchers at the Technion Israel Institute of Technology, revealed that quitting smoking may actually help boost muscle strength; the first evidence of its kind proving that ending your relationship with nicotine can physically make you stronger.
For all the smokers out there worried that quitting smoking is synonymous with weight gain, take note that a good portion of that weight is actually muscle! Researchers followed 81 smokers in Israel, finding that although they gained an average of 11 pounds (five kilograms) after quitting, 26 percent of that came in the form of bigger muscles. This is because smoking circulates carbon monoxide in your system, preventing your muscles from getting enough oxygen to use for energy. In fact the researchers found that, on average, those who quit smoking may be able to increase their strength by up to 20 percent.
To carry out the study, researchers tested the body composition and muscle strength in 41 heavy smokers who smoked at least 15 cigarettes a day. Their dietary intake and physical activity levels were estimated using questionnaires to ensure that they did not influence the results. Researchers began tracking this group immediately after they quit and then again a year later. About a quarter of participants were able to stay smoke-free throughout the whole year.
The body composition of each participant was measured using two different scanners, allowing for a fast, safe, and comfortable way to assess the breakdown of their fat, muscle and bone. The results were then used to determine total body fat percentage and changes in regional body composition.
Muscle strength was further evaluated by comparing chest press, leg press, and handgrip performance before and after the study. An analysis of the results shows that after one year, those who were able to wean off smoking gained an average of 11 pounds, while those who continued smoking gained less then two. Following analysis, it was shown that of the weight gained by those who quit, 74 percent was fat while the remaining 26 percent had transformed into pure muscle!
According to the researchers, quitters were able to regain a good deal of muscle due to the fact that tobacco significantly reduces oxygen availability to the muscles during exercise. Oxygen is important for the functioning of all energy systems in the body and therefore any mechanism that interferes with oxygen transport also interferes with energy production and athletic performance.
Strong enough to remain nicotine-free
As the study came to an end, researchers concluded that former smokers were stronger after quitting, achieving 17-23 percent more strength than those who continued to smoke. They also improved their bone mineral content and bone mineral density, a change that did not occur for the smokers.
We all know that there are many reasons to quit smoking. Quitting can help reduce risks of lung cancer, heart disease, and many other respiratory diseases, helps save you money and improve your lifestyle. Now there’s one more reason to add to the list; quitting smoking makes you stronger.
This study was co-authored by Prof. Dror Aizenbu chairman of the Department of Orthodontic and Craniofacial Anomalies at Rambam Health Care Campus, and Prof. Abraham Reznick, a molecular biophysicist at the Technion.