What exactly is meant by brisk walking? What is the pace that should be sustained? Some say it is that which is faster then a leisurely stroll. Some say that it requires that we increase our metabolic rate to three times that of sitting still. Other say that it should increase our heart rate to 70% of its maximum. The Centers for Disease Control recommend a pace in which you can talk but not sing. How are we able to figure this out? A study published in The British Journal of Sports Medicine put together the results of 38 previous studies that concentrated on the number of steps per minute, heart rates, respiration intensity, different ages and varying body mass indexes to try to come up with a number of steps per minute that would constitute brisk walking. What they came up with was 2.7 miles per hour or simply 100 steps per minute. How do we make this as simple as possible to figure out? Just count the number of steps you take in 6 seconds and multiply it by 10. Following this pace for 30 minutes should be enough for most people to maintain a healthy blood flow throughout their body.
Extreme mental focus such as preparing for an exam or just solving problems that require intense concentration can actually drain the brain. Since the brain has a limited capacity to store fuel, the results can be similar to using stored energy from caloric expenditure through physical movement. This is the reason why college students not only eat poorly but also overeat. Scientists experimented with thirty eight college students. After 35 minutes of sitting quietly in a peaceful setting to establish a baseline for what they would normally consume, all were given as much pizza as they wished. After a few weeks they were called back and were all given intense college exams that required extreme mental focus. Afterwards, half were given pizza to consume and half were put on a treadmill. The group on the treadmill consumed less than they would normally consume while the other group consumed much more. The increased flow of fuel-rich blood to the brain brought on by intense exercise increased both the amount of blood sugar and lactate circulating in the blood. This in turn reduced the desire to overeat by feeding an exhausted brain.
In Tanzania the people of the Hadza community have a diet that consists of the animals they kill, honey, berries and whatever grows wild. They eat what may be considered a true hunter-gatherer diet. In studying this group scientists have discovered that their gut bacteria undergoes different annual changes. Some of their microbes completely disappear only to return at another time of the year along with the change in diet. The study was conducted by the Max Plank Institute for Evolutionary Anthropology. Stool samples were compared with Italians from Bologna. The Hadza hosted much more abundant and rarer forms of gut microbial species. This led researchers to collect samples four times a year to see if the composition varied. There were extreme differences in the samples taken during the wet season as opposed to the dry season. This discovery is new for any human microbiome. The seasonal change in their diet lead to a predictable change in their gut bacteria. The composition is more similar to traditional older societies than to modernized industrial diets. Since industrialized nations eat the same foods year round, a clue to the rise in disease because of the loss of certain strains of bacteria may be the reason. This can be of significant value in possibly decreasing the causes of inflammation in the body, a source of chronic illnesses in our society. This would encourage us to explore more deeply the suggestion of a rotation of diet.
New studies show the relationship between healthy gut bacteria and how happy and anxious we feel. One study done by Canadian researchers gave cocktails of antibiotics to mice. The loss of the healthy bacteria brought on by the effects of the antibiotics made the animals more anxious. When gut bacteria was taken from healthy mice and transferred to these mice they appeared to become much calmer. More and more studies are being done on how gut bacteria can help with some brain disorders such as obsessive-compulsive disorder and ADHD. Because bacteria is thought to influence the immune system, a strong connection is now being made to both anxiety and depression. Fiber rich foods, especially from dark green leafy vegetables, provide nourishment for good bacteria to grow. This along with avoiding taking any unnecessary antibiotics can strengthen our gut and create peace of mind.