Reduce your risk of mortality, type 2 diabetes, depression, and bone loss
Slow your rate of biological aging and reduce craving for sugary snacks
Walking is one of the most accessible forms of physical activity. Be honest with yourself: Wouldn’t it be possible, and perhaps even enjoyable, to take a 22-minute walk every day? If so, you’d get the minimum amount of moderate-intensity physical activity that health authorities recommend. If so, you’d reduce your risk of multiple chronic conditions plus you’d probably feel better and enjoy better health as the following studies suggest.
First, how can you tell if you’re walking at a ‘brisk’ pace (moderate intensity exercise) as health experts recommend? A recent literature review showed that adults walking at a speed of 100 and 130 steps per minute equals moderate intensity and strenuous exercise, respectively. When walking, you can use the stopwatch on our cell phone and count the number of steps you take in 30 seconds. Double that number to find your number of steps per minute. If it’s greater than 100, you’re walking briskly.
The first published evidence of a link between level of physical activity following diagnosis of non-metastatic prostate cancer and risk of cancer-specific mortality appeared in 2011. A subsequent study used data from 1,455 men with diagnosed prostate cancer to extend the link with increased physical activity to risk of progression of prostate cancer. After 22 months of follow-up, men who reported walking briskly for more than three hours per week had significant 52 percent lower risk of prostate cancer progression compared to me who walked at an easy pace for less than 3 hours per week. Total non-vigorous activity and walking duration did not predict significantly reduced risk of progression.
Recent reports show that existing type 2 diabetes is reversible, especially in younger patients with diabetes of short duration. A prospective study in India followed 32 patients (average age 25 years) with newly diagnosed type 2 diabetes. All patients enrolled in lifestyle intervention therapy consisting of a restricted-calorie diet (1,500 calories per day) and one hour per day of brisk walking. Twenty-five patients of the 32 patients with HbA1c levels > 9% were also treated with metformin. Of the 32 patients, combined full and partial remission rates of type 2 diabetes at 3 months, 1 year, and 2 years were 75, 75, and 69 percent, respectively. Patients who reversed diabetes at three months consumed significantly fewer calories and had higher weight loss than those who did not reverse their diabetes. At three months, none of the patients who maintained or reduced their baseline weight has a recurrence of diabetes at two years. Two patients who regained 3-4 kg of weight between one and two years had a recurrence of diabetes. Thus, the combination of a restricted diet of 1,500 calories per day and one hour of daily brisk walking achieved high rates of full or partial remission of type 2 diabetes for most patients over two years. If you know a young adult with newly diagnosed type 2 diabetes, pass this info along.
Walking pace predicts life expectancy. Researchers in the UK used data from 474,919 participants with an average age of 58 years and an average body-mass index (BMI) of 26.7 in the UK Biobank Study to investigate the relative importance of physical fitness and body fat on life expectancy. Over an average follow-up of 7 years and compared to participants with a slow walking pace, those reporting a brisk walking pace had longer life expectancies, increasing from 86.7 to 87.8 years in women and from 85.2 to 86.8 years in men, regardless of BMIs. This study supports the “fat but fit” idea, namely that cardiorespiratory fitness predicts mortality better than fatness.
Faster walking pace predicts better health. But does faster walking pace predict longer white blood cell telomere length, a measure of biological aging? Researchers used data from 405,891 participants with an average age of 56 years in the UK Biobank Study to find out. Participants self-reported walking pace as slow, steady/ average, or brisk. Plus, a sub-sample of participants wore accelerometers to obtain objectively measured physical activity. Faster self-reported walking pace predicted longer telomere length, after adjusting for age, sex, ethnicity, and white blood cell count. Accelerometer data showed that more time spent in higher (brisk) walking intensity had a stronger link with telomere length than total physical activity. The increase in telomere length with brisk walking was equivalent to at least two fewer years of biological aging.
Exercise reduces urges for chocolate in normal weight people. But would exercise reduce these urges in overweight people? Researchers recruited 47 overweight persons with an average age of 28 years who regularly ate sugary snacks (at least 3.6 ounces per day) to answer this question. The participants were involved two research conditions, separated by one week. In one condition, participants were asked to warm up for 2 minutes then walk briskly for 15 minutes on a flat treadmill. In the other condition, participants sat quietly for 15 minutes. After both conditions, participants performed a stressful task then unwrapped and handled a sugary snack of their choice. Exercise reduced food craving compared to the quiet sitting. Overweight persons may curb their snacking behavior with small periods of brisk walking.
Depression creates more medical burden that any other form of mental illness. Abundant research shows that increased physical activity predicts reduced risk of depression. Yet, the shape of the relationship between increased physical activity and the rate of decline in risk of depression remains unknown. Researchers in the UK conducted a systematic review and meta-analysis of 15 published studies that investigated at least three levels of physical activity in relation to risk of depression and increased depressive symptoms. Analyses showed a declining risk of major depression as physical activity increased to about 22 minutes of brisk walking per day. Participants who got the equivalent of 22 minutes of brisk walking per day had 25 percent lower risk of major depression compared to participants who reported no physical activity.
Here’s more good news: Even participants who got the equivalent of 11 minutes of brisk walking per day had 18 percent lower risk of major depression. Similarly, risk of increased depressive symptoms declined as physical activity increased to about 22 minutes of brisk walking per day, after which further decrease in risk slowed considerably. This study reprises many other studies that show significant mental health benefits of increased physical activity.
Hormonal changes predispose menopause women to lose bone mass and strength, which increases their risk of osteoporosis and hip and leg fractures. Strength-building exercises can increase bone mineral density (BMD) in older women. Yet, older women often won’t participate in strength-building or other organized or gym-based physical activities. Perhaps tai chi or brisk walking might be more palatable to older women. Researchers recruited 75 perimenopausal women aged 45-55 years to participate in 48 weeks of supervised brisk walking or tai chi three times each for about 50 minutes per session. A third of the participants served as a no-exercise control group.
After 48 weeks and compared to baseline, participants in the brisk walking significantly increased their femoral neck BMD by 8.23 percent. Eight weeks after the program ended, the BMD of the femoral neck in participants in the brisk walking group was still significantly greater (9.41 percent) than that at baseline. After 48 weeks and compared to baseline, participants in the tai chi group significantly increased their lumbar spine BMD by 5.05 percent. Eight weeks after the program ended, the BMD of the lumbar spine in participants the tai chi group was still significantly greater (5.05 percent) than that at baseline. Thus, both brisk walking and tai chi can help middle-aged women reduce their loss of bone mass.
Can’t you find 22 minutes each day for a brisk walk that might reduce your risk of mortality, type 2 diabetes, craving sugary snacks, depression, and bone loss?