We know that spending hour after hour sitting down isn’t good for us, but just how much exercise is needed to counteract the negative health impact of a day at a desk? A 2020 study suggests about 30-40 minutes per day of building up a sweat should do it.
Up to 40 minutes of “moderate to vigorous intensity physical activity” every day is about the right amount to balance out 10 hours of sitting still, the research says – although any amount of exercise or even just standing up helps to some extent.
That’s based on a meta-analysis across nine previous studies, involving a total of 44,370 people in four different countries who were wearing some form of fitness tracker.
The analysis found the risk of death among those with a more sedentary lifestyle went up as time spent engaging in moderate-to-vigorous intensity physical activity went down.
“In active individuals doing about 30-40 minutes of moderate to vigorous intensity physical activity, the association between high sedentary time and risk of death is not significantly different from those with low amounts of sedentary time,” the researchers wrote in the British Journal of Sports Medicine (BJSM) in 2020.
In other words, putting in some reasonably intensive activities – cycling, brisk walking, gardening – can lower your risk of an earlier death right back down to what it would be if you weren’t doing all that sitting around, to the extent that this link can be seen in the amassed data of many thousands of people.
While meta-analyses like this one always require some elaborate dot-joining across separate studies with different volunteers, timescales, and conditions, the benefit of this particular piece of research is that it relied on relatively objective data from wearables – not data self-reported by the participants.
“These guidelines are very timely, given that we are in the middle of a global pandemic, which has confined people indoors for long periods and encouraged an increase in sedentary behavior,” said physical activity and population health researcher Emmanuel Stamatakis from the University of Sydney in Australia.
“People can still protect their health and offset the harmful effects of physical inactivity,” says Stamatakis, who wasn’t involved in the meta-analysis but is the co-editor of the BJSM. “As these guidelines emphasize, all physical activity counts and any amount of it is better than none.”
The research based on fitness trackers is broadly in line with the new WHO guidelines, which recommend 150-300 mins of moderate intensity or 75-150 mins of vigorous-intensity physical activity every week to counter sedentary behavior.
Walking up the stairs instead of taking the lift, playing with children and pets, taking part in yoga or dancing, doing household chores, walking, and cycling are all put forward as ways in which people can be more active – and if you can’t manage the 30-40 minutes right away, the researchers say, start off small.
Making recommendations across all ages and body types is tricky, though the 40 minute time frame for activity fits in with previous research. As more data are published, we should learn more about how to stay healthy even if we have to spend extended periods of time at a desk.
“Although the new guidelines reflect the best available science, there are still some gaps in our knowledge,” said Stamatakis.
“We are still not clear, for example, where exactly the bar for ‘too much sitting’ is. But this is a fast-paced field of research, and we will hopefully have answers in a few years’ time.”
The research was published here, and the WHO guidelines here, in the British Journal of Sports Medicine.
Athletes have a very complicated relationship with pain. For endurance athletes in particular, pain is an absolutely non-negotiable element of their competitive experience. You fear it, but you also embrace it. And then you try to understand it.
But pain isn’t like heart rate or lactate levels—things you can measure and meaningfully compare from one session to the next. Every painful experience is different, and the factors that contribute to those differences seem to be endless. A recent study in the Journal of Sports Sciences, from researchers in Iraq, Australia, and Britain, adds a new one to the list: viewing images of athletes in pain right before a cycling test led to higher pain ratings and worse performance than viewing images of athletes enjoying themselves.
That finding is reminiscent of a result I wrote about last year, in which subjects who were told that exercise increases pain perception experienced greater pain, while those told that exercise decreases pain perception experienced less pain. In that case, the researchers were studying pain perception after exercise rather than during it, trying to understand a phenomenon called exercise-induced hypoalgesia (which just means that you experience less pain after exercise).
This phenomenon has been studied for more than 40 years: one of the first attempts to unravel it was published in 1979 under the title “The Painlessness of the Long Distance Runner,” in which an Australian researcher named Garry Egger did a series of 15 runs over six months after being injected with either an opioid blocker called naloxone or a placebo. Running did indeed increase his pain threshold, but naloxone didn’t seem to make any difference, suggesting that endorphins—the body’s own opioids—weren’t responsible for the effect. (Subsequent research has been plentiful but not very conclusive, and it’s currently thought that both opioid and other mechanisms are responsible.)
But the very nature of pain—the fact that seeing an image of pain or being told that something will be painful can alter the pain you feel—makes it extremely tricky to study. If you put someone through a painful experiment twice, their experience the first time will inevitably color their perceptions the second time.
As a result, according to the authors of another new study, the only results you can really trust are from randomized trials in which the effects of exercise on pain are compared to the results of the same sequence of tests with no exercise—a standard that excludes much of the existing research.
The new study, published in the Journal of Pain by Michael Wewege and Matthew Jones of the University of New South Wales, is a meta-analysis that sets out to determine whether exercise-induced hypoalgesia is a real thing, and if so, what sorts of exercise induce it, and in whom. While there have been several previous meta-analyses on this topic, this one was restricted to randomized controlled trials, which meant that just 13 studies from the initial pool of 350 were included.
The good news is that, in healthy subjects, aerobic exercise did indeed seem to cause a large increase in pain threshold. Here’s a forest plot, in which dots to the left of the line indicate that an individual study saw increased pain tolerance after aerobic exercise, while dots to the right indicate that pain tolerance worsened.
The big diamond at the bottom is the overall combination of the data from those studies. It’s interesting to look at a few of the individual studies. The first dot at the top, for example, saw basically no change from a six-minute walk. The second and third dots, with the most positive results, involved 30 minutes of cycling and 40 minutes of treadmill running, respectively. The dosage probably matters, but there’s not enough data to draw definitive conclusions.
After that, things get a little tricker. Dynamic resistance exercise (standard weight-room stuff, for the most part) seems to have a small positive effect, but that’s based on just two studies. Isometric exercises (i.e. pushing or pulling without moving, or holding a static position), based on three studies, have no clear effect.
There are also three studies that look at subjects with chronic pain. This is where researchers are really hoping to see effects, because it’s very challenging to find ways of managing ongoing pain, especially now that the downsides of long-term opioid use are better understood. In this case, the subjects had knee osteoarthritis, plantar fasciitis, or tennis elbow, and neither dynamic nor isometric exercises seemed to help. There were no studies—or at least none that met the criteria for this analysis—that tried aerobic exercise for patients with chronic pain.
The main takeaway, for me, is how little we really know for sure about the relationship between exercise and pain perception. It seems likely that the feeling of dulled pain that follows a good run is real (and thus that you shouldn’t conclude that your minor injury has really been healed just because it feels okay when you finish).
Exercise-associated muscle cramps (EAMC) are defined as cramping (painful muscle spasms) during or immediately following exercise. Muscle cramps during exercise are very common, even in elite athletes. EAMC are a common condition that occurs during or after exercise, often during endurance events such as a triathlon or marathon.
Although EAMC are extremely common among athletes, the cause is still not fully understood because muscle cramping can occur as a result of many underlying conditions. Elite athletes experience cramping due to paces at higher intensities.The cause of exercise-associated muscle cramps is hypothesized to be due to altered neuromuscular control, dehydration, or electrolyte depletion.
It is widely believed that excessive sweating due to strenuous exercise can lead to muscle cramps. Deficiency of sodium and other electrolytes may lead to contracted interstitial fluid compartments, which may exacerbate the muscle cramping. According to this theory, the increased blood plasma osmolality from sweating sodium losses causes a fluid shift from the interstitial space to the intervascular space, which causes the interstitial fluid compartment to deform and contributes to muscle hyperexcitability and risk of spontaneous muscle activity.
The second hypothesis is altered neuromuscular control. In this hypothesis, it is suggested that cramping is due to altered neuromuscular activity. The proposed underlying cause of the altered neuromuscular control is due to fatigue. There are several disturbances, at various levels of the central and peripheral nervous system, and the skeletal muscle that contribute to cramping.
These disturbances can be described by a series of several key events. First and foremost, repetitive muscle exercise can lead to the development of fatigue due to one or more of the following: inadequate conditioning, hot and or humid environments, increased intensity, increased duration, and decreased supply of energy. Muscle fatigue itself causes increased excitatory afferent activity within the muscle spindles and decreased inhibitory afferent activity within the Golgi tendon.
The coupling of these events leads to altered neuromuscular control from the spinal cord. A cascade of events follow the altered neuromuscular control; this includes increased alpha-motor neuron activity in the spinal cord, which overloads the lower motor neurons, and increased muscle cell membrane activity. Thus, the resultant of this cascade is a muscle cramp.
Can’t bend over and touch your toes? You might think flexibility is something you’re born with — you either have it or you don’t. While your flexibility level does have ties to genetics (we can’t all be contortionists), you might be surprised to learn that you can build flexibility just as you can build strength, endurance or speed.
Just like anything else, developing flexibility takes practice. It takes just as much consistency as does building muscle or getting in shape for a marathon. It may not be easy, but it’s definitely doable, and you can get started with these simple ways to become more flexible.
Holding static stretches may be the simplest method to improve flexibility. Static stretching includes all flexibility exercises that involve holding a muscle in a stretched position for a substantial amount of time, usually around 30 seconds. This allows you to isolate and deeply stretch a muscle. Starting and ending your day with static stretches — just for 5 to 10 minutes — can make a big difference in how flexible your muscles feel on a daily basis.
Static stretches you might already be familiar with include:
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2. Perform dynamic stretches before and after you exercise
Dynamic stretches, in contrast to static stretches, continuously move your muscles and joints through their full range of motion. This type of stretching feels much more vigorous than static stretching and may even get your heart rate up.
Dynamic stretching doesn’t isolate muscles as much as static stretching; rather, this type of active stretching works multiple muscles at the same time and teaches you how to engage your muscles and joints to support deeper and more fluid motion. Performing dynamic stretches before your workout makes for a good warmup, and engaging in a few after your workout helps return your body to its resting state (rather than just stopping cold after an intense sweat).
You might feel inflexible due to adhesions in your fascia, a type of connective tissue that covers your muscles, bones and joints. What people refer to as “muscle knots” often actually occur in the fascia (though your muscle tissue can develop knotty areas, too).
If you have a lot of these adhesions, which can develop from long periods of sedentary behavior as well as from intense physical activity, try adding self-myofascial release to your routine. Self-myofascial release is essentially self-massage with the goal of “releasing” those tight knots from your body tissues. You can do self-myofascial release with a foam roller, a lacrosse ball, a muscle roller or a massage gun.
Your ability or inability to fully rotate your spine and ball-and-socket joints (hips and shoulders) greatly influences your overall flexibility level. Your spine, hips and shoulders dictate most of the movements you make on a daily basis whether you realize it or not: Every time you step, reach, bend, turn, sit or stand, you’re using your spine along with your hips or shoulders. If you don’t actively practice rotating these joints, you’re missing out on your potential for flexibility.
Try these rotational exercises to improve flexibility:
In addition to your usual exercise, such as lifting weights or walking, try dedicating a few minutes each day to flexibility training. Time constraints may make it hard to prioritize flexibility exercises, but if you really want to get bendy, you’ll have to commit to a regular practice.
Here’s one way to incorporate flexibility training into your workout routine:
Morning: 5 minutes of static stretching, focus on the lower body
Before workout: 10 minutes of full-body dynamic stretching
After workout: 5 minutes of myofascial release on the muscles you worked
Before bed: 5 minutes of static stretching, focus on the upper body
By dedicating just a few minutes at a time, you can achieve nearly half an hour of flexibility training each day you exercise.
You can always slightly cut back on your active exercise time to incorporate flexibility work. For example, if you usually walk for 60 minutes a day, walk for 50 minutes and end your walk with 10 minutes of stretching. In the end, becoming more flexible is all about prioritizing flexibility as a goal.
The information contained in this article is for educational and informational purposes only and is not intended as health or medical advice. Always consult a physician or other qualified health provider regarding any questions you may have about a medical condition or health objectives.
Some fast-paced, high-pressure workplaces take a physical toll on their workers. This is counterproductive to the employers because it decreases worker productivity and increases costs. For the employees, they may be literally working themselves to death. Some of the physical effects of an unhealthy workplace include:
1. Carpal Tunnel Syndrome
According to the Mayo Clinic, carpal tunnel syndrome can be caused by conditions in the workplace that cause repetitive flexing of the wrist, which can damage the median nerve or exacerbate any existing damage. Carpal tunnel syndrome can affect workers who use computers all day, grocery checkers, and assembly line workers, especially if you work in a cold environment.
2. Back Injuries
The main causes of back injuries in the workplace include inadequate training, improper lifting technique, rushing, and a skewed perception of the risks involved with lifting. Once you injure your back, you are significantly more likely to experience another back injury in the future. Employers need to make sure employees who lift have safety gear and are well-trained.
3. Illnesses From Exposure to Toxins
Exposure to toxic substances on the job can cause respiratory, renal, cardiovascular, and reproductive harm. The Occupational Safety and Health Administration (OSHA) requires employees to have protocols in place to reduce workers’ exposure to chemical hazards and toxic substances. Any violation of these standards should be reported to OSHA.
Working long hours can increase your risk of developing high blood pressure, which is also known as hypertension. This condition can have serious effects on your health including aneurysm, strokes, heart damage, kidney failure, and even damage to your vision. If you’re working overtime, you may need to cut back your hours to protect your health.
According to OSHA, fatigue can have serious health effects. Aside from reducing your alertness and impairing your ability to make decisions, it can affect your memory and your ability to concentrate. It can also cause you to be irritable and unmotivated. Workplace fatigue can be deadly if you are a driver or you work with machinery, and it can also cause heart problems.
6. Digestive Issues
Workplace fatigue can also cause digestive problems that have symptoms similar to those experienced with irritable bowel syndrome. These can include diarrhea, nausea, constipation, and bloating. These symptoms can also be caused by stress in the workplace. Work stress can also cause you to produce excess stomach acid, leading to indigestion and heartburn.
Depression, stress, and anxiety at work can lead to the development of type 2 diabetes, and there is no cure for this condition. When you’re under stress, your body may not release its insulin. This will eventually cause an excess of glucose in your blood. The longer you’re under stress for, the higher your glucose levels will become.
8. Injuries From Accidents or Explosions
Millions of Americans are injured in non-fatal workplace accidents each year, and approximately 5,000 workers are killed on the job annually. Slip, trip, and fall accidents, fires, explosions, and violence cause many disabilities. They also cost employers millions of dollars. Most of these are preventable injuries that wouldn’t have happened with better training and equipment.
Any of these physical effects of toxic workplaces can lead to lost wages, missed work, and in the most serious cases the permanent inability to work. If you’re experiencing any of these health conditions due to your job, you’re in an unhealthy work environment.