Middle-Age Fitness Links to Healthy Aging and Lower Cancer Risk
Cancer is primarily a disease of age. The older we get the higher our risk for cancer along with other chronic diseases. Now a study published last week sheds light on how our activity habits throughout life make a difference in preventing diseases such as cancer, and living healthier as we age.
The study looked at how physical fitness in mid-life linked to the onset of chronic illness. It was published online in the Archives of Internal Medicine.
“Previous studies have shown a link with fitness and an extension of lifespan but there’s almost no data looking at fitness and non-fatal outcomes,” said senior author Jarrett Berry, MD, MS, an assistant professor of internal medicine at University of Texas Southwestern Medical Center. “We wanted to create a proxy for healthy aging in a large dataset, and if you have fewer chronic conditions, you are aging more healthfully.”
Fitness Delays Disease and Time with Disease
Berry and his colleagues first gathered fitness data from almost 19,000 participants of the Cooper Center Longitudinal Study. Participants were healthy when they entered the study in their 30s, 40s, and 50s, and the study categorized their fitness levels through a treadmill test.
Researchers then merged the fitness data with participants’ Medicare claims that spanned an average of 26 years. The study focused on claims for eight chronic conditions, including the lung and colorectal cancers. (One reason these cancers were selected is because they affect both men and women.) Other illnesses the study looked at included stroke, diabetes, congestive heart failure, Alzheimer’s and kidney disease.
By the end of the study period, approximately 2,500 participants had died and the researchers looked at the last five years of their lives.
Both among men and women, participants who were more fit in midlife had a decreased risk of developing colon cancer, diabetes or any of the other chronic conditions later in life.
Among those who did develop a disease, individuals who were fitter in middle age lived their final five years with fewer chronic conditions. The findings suggest that fitness compresses the disease into a shorter amount of time at the end of life, giving people a longer healthier life, says Berry.
Getting off the Couch
“We saw a link between fitness and the delay of chronic conditions,” said Berry. “On average, people who had low fitness in mid-life, spent more of their time with more chronic disease than people with higher fitness levels.”
The delay of chronic disease was highest among those who were the most fit – those categorized in the fifth of the five fitness categories. Yet the most prominent change in decreased risk was between the lowest fitness level category and those slightly more fit, in the category right above.
“What this shows is that the healthy benefit is greatest for those who are sedentary who initiate some exercise,” said Berry. “It’s not going from a couch potato to marathon runner, the greatest benefit comes from coach potatoes who get off the couch – when you move from a sedentary to a modest activity level.”
The study did not account for other factors that may play a role in disease, such as genetics or diet. It did account for obesity, blood pressure, cholesterol levels, alcohol use and smoking.
“We focus on the present… thinking more about time and age is an incredibly important concept that I think has big implications,” said Berry.
The It’s-Never-Too-Late Approach
This study is part of a growing area of research spotlighting how diet, activity and other factors even in mid-life still affect risk of getting cancer and other chronic diseases. The research suggests that lifestyle habits throughout life can play a key role in cancer risk.
“We know colon cancer and some other cancers can take decades to develop so it makes sense that what people are eating and how much they are moving throughout their lives can affect the development of cancer later in life,” said AICR Director of Research Susan Higginbotham, PhD, MPH, RD.
Government guidelines for physical activity recommend adults should be aerobically active at a moderate intensity for at least 150 minutes per week and do muscle strengthening activities at least two days a week. For cancer prevention, AICR recommends adults be active at a moderate intensity for at least 30 minutes a day.
Researchers are also looking into how lifestyle habits from infancy to adolescence affect future cancer risk. Read Preventing Cancer: The Life Course Approach for more.
Published on September 5, 2014