воскресенье, 28 августа 2016 г.

Энергия в организме. Откуда берется энергия во время диеты

 
 
Откуда же мы берем энергию? На самом низком уровне клеточной функции, ту форму энергии, которую ваши клетки могут использовать, называется аденозин трифосфат (АТФ). 

Для нашей большей пользы, тело производит АТФ посредством сжигания (окисление или сгорание) глюкозы из углеводов, либо жирных кислот из жиров. При определенных обстоятельствах, белок тоже может использоваться для воссоздания АТФ, непосредственно либо с помощью преобразования в глюкозу или жир (обычно белок конвертируется в глюкозу, чтобы использоваться как топливо). Чуть позже мы вернемся к этому. 

Учитывая некоторые исключения, о которых я скажу через несколько секунд, каждая ткань в организме, может использовать как углеводы, так и жир для энергии. Но что определяет какой вид топлива будет использоваться? Когда углеводы доступны (потому что вы едите больше всего именно их), тогда ткани будут использоваться углеводы, в виде глюкозы, для топлива. Когда углеводы недоступны (потому что вы ограничили себя), тело переключится на использование жиров. Этот жир может быть использован как из вашей пищи, так и из вашей задницы и живота. Это еще один нюанс, который чаще всего забывают при использовании методов для сброса веса/жира: когда вы потребляете больше углеводов, то ваше тело использует меньше энергии из жира, когда же вы едите меньше углеводов, ваше тело использует больше энергии из жира. 

А что на счет исключений? Некоторые ткани в вашем теле, такие как мозг/ЦНС и парочка других, не могут использовать жирные кислоты в качестве энергии, они могут потреблять лишь глюкозу. И мозг это самое важное, о чем я хочу поговорить здесь. Как обычно (и это неверно) водится, что мозг может использоваться лишь глюкозу в качестве энергии, и это действительно так, если вы рассматриваете глюкозу, аминокислоты и жир как источники энергии. Но таким образом мы забываем о четвертом источнике энергии – кетоны (так же известны как кетоновые тела). Кетоны созданы из расщепления жира посредством работы печени и выполняют работу топлива для мозга в период голодания или урезания углеводов. 

Я хочу заметить, что после нескольких недель кетоза (состояние, в котором кетоны накапливаются в крови в качестве топлива, которое использует мозг), мозг может получать порядка 75% всей основной энергии из кетонового обмена веществ. Остальные 25% приходятся на глюкозу.

This Man Stretched 10 Minutes a Day for a Month. Here’s What Happened

 

Turns out, a loose muscle is a strong muscle.

  
Modified Pigeon
PHOTOGRAPH BY BEN GOLDSTEIN
Like most guys, I hated stretching. Why waste time sitting around when I could be out running?
It hurt to learn that I was wrong—throbbed like hell, actually. I hurt my hiptrying a leg workout and going running the same day, and had to shut down.
I called Doug Kechijian, D.P.T., of Resilient Performance Physical Therapy in New York City. A stretching expert, he told me that everyone has imbalances and mobility restrictions. We sit too much and don’t put our bodies into enough different positions.
His prescription? Ten minutes a day of mobility moves.
They felt more like kung fu than calisthenics. Take the modified pigeon stretch.
“Most people stand with their hips shifted to the right, which causes their left hip to tighten up,” Kechijian says. This pose helps redistribute that weight.
As I sank into it, the painful area in my hip felt like it was being pulled apart—in a good way.
Other moves seemed meant for contortionists. Instead of reps, each was done for a series of extremely deep breaths, a signal for your body to release muscle tightness.
I felt relief after the first day, so I kept the circuit up. On gym days it was my warmup. On rest days, I did it in the office or at home in front of the TV. I ignored the odd looks from my coworkers and girlfriend, who dubbed Kechijian “the witch doctor.”
It was totally worth it. Within a month my pain was a memory. 
Then one night, as I sank into the pigeon pose, I noticed my girlfriend staring at me. “Damn, the witch doctor got you jacked,” she said.
Want to get mobilized? Try the stretching moves below. You need just 10 minutes. That’s not a tough stretch.
Here’s how to do it: Perform each exercise every day for the prescribed time or number of reps. Do them before runs, and intermittently throughout your workday or while winding down on your rest days, says Doug Kechijian, D.P.T., who created this routine.
Counterweight Deep Squat
PHOTOGRAPH BY BEN GOLDSTEIN
Counterweight Deep Squat
Grab two light dumbbells and place a foam roller between your thighs. Push your knees forward and then squat until your butt is just above the floor. (Use the lightest weight that allows you to achieve this position.) Try to round your spine by “tucking” your pelvis. From that position, take 5 long, deep breaths. Stand back up. That’s 1 rep. Do 3 to 5.
Modified Pigeon
PHOTOGRAPH BY BEN GOLDSTEIN
Modified Pigeon
Get down on all fours and place a pillow or foam roller under your left knee. Lift your right knee and place it behind and to the left of your left calf. Rock your hips back and forth for 2 minutes. You should feel your left hip stretch. Switch sides and repeat.
lat hang
PHOTOGRAPH BY BEN GOLDSTEIN
Lat Hang
Hang from a pullup bar. Squeeze your glutes to slightly tilt your pelvis forward. Breathe in deeply. Breathe out as much air as you can—you should feel your lats stretch. Take 5 deep breaths. That’s 1 rep. Do 3 to 5.
Michael Easter is the Fitness Editor of Men’s Health. The article This Man Stretched 10 Minutes a Day For a Month. Here’s What Happened originally appeared on Men’s Health

It's All in the Hips

 

Foot strike, the darling of minimalism, is overrated. Good form starts with the pelvis and the glutes.

  
Watch a video of Kenenisa Bekele winning a 5,000m or 10,000m, and it is quickly apparent that he and the rest of the world-class pack with him are doing something different from what most of us do every day. They float around the track, hardly seeming to touch it. They accelerate smoothly and effortlessly. Their legs seem to spin beneath weightless bodies.
We want to run like them, but too often we feel like we're muscling our bodies along, pounding the ground and working for each forward push. What element of their stride creates the difference? Where should we look?
For the past several years, we've been told to focus on their feet. Elite runners are different, form experts have said, because they land on their midfoot or forefoot, and we should do the same to run more smoothly, faster and with less injury. Where your foot makes contact with the ground became a litmus test of running prowess. Among some runners, the label "heel-striker" attained the stigma of "learning impaired."
And yet, many of those who adopted a forefoot strike and the minimalist shoes that accompanied the movement didn't see an improvement in times and continued to get injured. So much so that the movement has all but disappeared.
A wide range of experts--from kinesiologists to physical therapists, orthopedists to coaches--agree that the extreme emphasis the running world has put on foot strike is misplaced. Daniel Lieberman, the Harvard scientist who gave scientific credence to minimalism with his seminal 2010 article in Nature, says, "Frankly, when we published that paper, I never expected everyone to obsess about it as much as they did. Had I realized that, I would have added a sentence to the effect that while foot strike is important, there are many other important aspects of form as well. I have learned over the years that the worst thing to tell anyone is to forefoot strike."
Grant Robison, an elite runner and coach whose Good Form Running program was adopted by New Balance to educate runners on how to move into the company's Minimus line, says that while teaching runners to land on the midfoot was an emphasis a few years ago, he now considers it the least important of the four points he teaches: Posture, Mid-Foot, Cadence and Lean. "I draw people's attention to it, showing that if you can use more of your foot, things don't get stressed as much, but then I kind of let that be," Robison says.
But the minimalist movement wasn't wrong in suggesting that most of us need to improve our form if we are to run like Bekele. Trying to change how we land, however, didn't address the big goals of shifting our balance forward and moving our stride more behind than in front of us--essential elements of those effortless elite movement patterns we desire.
The emphasis on foot strike missed the mark by putting the attention on the end of the chain, rather than the beginning. We need to shift our focus upward to our hips and glutes, where the stride begins.
"More often than not, I see foot strike as simply being the end result of so many other things that are happening farther up the kinetic chain," says David McHenry, physical therapist and strength coach for Alberto Salazar's Nike Oregon Project. "The foot is really just the end of a big kinetic whip--the leg. Core and hips are where every runner should be starting if they are really concerned with optimizing their form, maximizing their speed and minimizing injury potential."
Jay Dicharry, physical therapist and director of the REP Biomechanics Lab in Oregon, agrees that foot strike is an effect, not a cause. He's measured heel-strikers who touch down with zero force and forefoot strikers who pound the ground. "There are many ways to move correctly," Dicharry says. But he sees similarities in all who move efficiently and powerfully. "If you can keep your posture in check and keep your hip drive up, you're going to run really, really well."
In sum, the experts say, mind your hips and your feet will take care of themselves.
FAULTY FULCRUMS
What is it we want our hips to do? The key elements are balance and drive. Our torsos balance on our hips, and the hips are the fulcrums of the leg levers driving our bodies forward. If they are not working properly, the legs are unable to provide optimal power and speed. And many of us have trouble using them properly, resulting in all sorts of inefficiencies. The most common is overstriding: reaching forward and landing in front of the torso.
We don't overstride, however, simply because we wear overbuilt shoes and have learned poor running habits. We do it because our lifestyles outside of running create inflexibilities, weaknesses and poor balance. These are reinforced while running, such that now many of us are physically incapable of striding out naturally, with our legs behind our center of gravity. "We are not living the lives our bodies were designed for," says Irene Davis, a professor at Harvard Medical School and director of the Spaulding National Running Center. Bobby McGee, a Boulder, Colo.-based running coach who led Josia Thugwane to gold in the 1996 Olympic marathon, says the goal is to get back to how we moved as 9- or 10-year-olds, before environmental circumstances changed our patterns.
Heading to the gym to attack these weaknesses often doesn't correct them, however. Strengthening exercises will do little good without changing how we move and recruit our muscles. "Research has shown that strengthening alone--without retraining movement patterns--does not alter mechanics," Davis says. "The individual must own the new pattern, or it will not be durable."
Before we can own it, we need to feel it.
PELVIC PROPRIOCEPTION
It all starts with proper posture, the experts say. Proper posture is what makes some athletes look graceful and light on their feet, balanced and agile. McGee calls it "getting connected." GP Pearlberg, an author and online coach, calls it "running tall."
Whatever we call it, learning it takes more than trying not to slouch or sucking in our guts. Good posture is not the stilted, rigid position we adopted when our mothers yelled, "Sit up straight!" We cannot imagine maintaining this pose for long while sitting or standing, let alone running, so too often we dismiss calls for better posture.
To get away from old ideas of posture, it might help to think of it as "hip proprioception," a fancy term that Trent Nessler, a physical therapist and the CEO of Accelerated Conditioning and Learning, uses to mean our awareness of what is going on with our hips, both the position of the bones and the muscles that are firing around them. Dicharry's book Anatomy for Runners centers around this concept. "It comes down to awareness and feel," Dicharry says, noting that people who have habitually poor posture "don't respond to cues like 'run tall' and 'keep your spine in neutral.' They pretty much have no idea they have a spine, or a hip, or any muscles that control them at all."
How do runners learn pelvic proprioception? The first test is vertical compression. Try the test below now.
HIP POSITION TESTS
IMAGE BY CHARLIE LAYTON
HIP TEST 1Vertical compression
While standing, have someone behind you put their hands on your shoulders and push straight down. If your body buckles at the back and hips, you know your hips and balance are off.
You can correct this buckling by changing your balance and posture. To find this new balance, one method is to reach up as high as you can as if trying to get something off a high shelf, then lower your arms without changing hip and back position. Another method is to place one hand on your belly button and one on your sternum, then, without moving the belly-button hand, bring your sternum forward until your weight is balanced over your hips and equally distributed between your forefoot and heel. Now have someone push down on your shoulders again: You should be able to withstand considerable force comfortably.
In adjusting your posture to achieve a balanced state, you likely noted your pelvis position rotated. A second test can help you feel this rotation better.
IMAGE BY CHARLIE LAYTON
HIP TEST 2Hip extension
Stand in front of a doorway with your back against the right side of a doorjamb and your left leg in the doorway opening. Kneel with your left knee on the floor inside of the doorjamb and your right knee above your right foot in front of you. Your left thigh should be vertical beside the doorjamb, with your back resting against the front of the doorjamb. In this position, you'll naturally have a bit of space between your lower back and the wall. Tilt your pelvis backward so the hollow between your lower back and the doorjamb disappears. Your pelvis should rotate up in front and down in back.
THE TIPPING POINT
If you think of your pelvis as a bowl, hinged at the hip bones and controlled by the muscles in front and in back, your goal is to keep the bowl neutral and not "spill" either way. (Most of us spill out the front.) The image helps keep the pelvis aligned so you can ride better above it with the hips more "stacked under the torso," McHenry says, describing the goal of his recent work with high school phenom Mary Cain. When you are able to keep the bowl from spilling--even while working hard on a run--you begin to feel the connected power as your leg drive pushes your body forward, rather than twisting your hips forward, arching your back and losing energy in the torquing.
If you have trouble completing the rotation in the hip extension test (above) or feel tightness in the front of your hip and down the front of the thigh, your hip flexors are too tight. You are not alone. Dicharry says 85 percent of runners have tight hip flexors. McGee names it as the first issue to address in improving form. This tightness contributes to the pelvis "spilling" forward, throws off the balance and prevents the leg from driving backward.
Our hours of sitting--at our desks, driving, relaxing--shorten and tighten our hip flexors on the front of the pelvis and turn off our glutes on the backside. When we stand up, we never fully open up, retaining some of a sitting posture in our hips. Running optimally, however, like elite track stars, involves driving the leg back from the hip, requiring a full hip extension. The faster we want to run, the more important this is.
REAR ENGINE
IMAGE BY PETER CROWTHER
To have a hip drive like the elites requires not only mobility, but also strong, active glutes. Experts agree that glutes are the most powerful, efficient movers for running, and failing to use them creates serious problems. "A strong butt is the key to a happy life," says Jordan Metzl, a sports medicine physician at the Hospital for Special Surgery in New York. Runners with weak glutes fall into the "toilet bowl of doom--a beautifully engineered screw-up of epic proportions," Dicharry says. Posture falls apart, the stride has to move in front of the torso, and other muscles compensate until they fail.
Like balance and hip position, however, the first thing we need to do is to learn to feel the glutes and know that they are firing.
GLUTE TESTS - Three ways to get your butt in gear:
IMAGE BY CHARLIE LAYTON
GLUTE TEST 1: The bridge
Lie on your back with your knees up and your feet flat on the ground. Hold your arms straight out above you. Lift your hips up to make a straight bridge from shoulders to knees. Where do you feel it? If you feel stress anywhere but your butt, you aren't activating your glutes. Rock your hip angle and change your back arch so that you don't feel the effort in your back or your hamstrings but in the center of your butt. One way to ensure this is to have someone push down hard or place a weight on the front of your pelvis. You won't be able to hold it if you aren't using your glutes. If you have trouble isolating the glutes, try first pulling one knee to your chest, which locks out the back's ability to arch, then do a single-leg bridge.
IMAGE BY CHARLIE LAYTON
GLUTE TEST 2Pigeon hip extension
Get on your hands and knees. Reach one leg straight back, then lower that knee to the ground while dropping your upper body to your elbows over the other leg tucked beneath you. Clench your butt cheeks together, then raise the back knee to straighten the leg without lifting your toes. Feel the glute on your back leg.
IMAGE BY CHARLIE LAYTON
GLUTE TEST 3: Standing hip extension
Stand on one leg with the other held so the calf is parallel to the ground. Hold your hands on your hips, wrapping around the front. Drive the lifted foot backward into an imaginary wall, without allowing your pelvis to rotate forward or your spine to tip. Feel your glute activate and your hip flexor stretch as it extends.
GLUTE GOOSE
After learning what it feels like for your glutes to contract, start noticing if they are working when you're running. Tom Miller, an exercise scientist and author of Programmed to Run, calls the feeling when you get it right a "glute goose" or a "hip flick" with every stride. Others call it running "from the butt." When it clicks, you can feel the glute pulling your thigh and knee back while your hips remain stable and connected, channeling the energy of the leg drive into forward motion.
You can strengthen your glutes with numerous exercises like the bridge (or advanced options like one-leg bridges and marching bridges), donkey kicks, single-leg dead lifts, and squats. But you should only advance in doing these when you are confident that you are using your glutes, to ensure that they are the muscles working and not the muscles around them. If you are feeling the stress in your back, hamstrings or quads instead of your butt, you are likely reinforcing the imbalances you hope to correct.
HABIT-FORMING
McGee says that while duration creates strength, frequency makes skill. To improve your skill, you must work at it often. The good news is that you can work on many of these skills all day, every day. You can play with your balance and hip proprioception while standing in line at the coffee shop, cue glute activation when walking, and do hip extension stretches, glute strengthening exercises or one-leg balancing while reading email, on a conference call or watching TV.
Dicharry has seen many runners learn to use their hips in exercises but then instantly revert to old patterns as soon as they start running or when they speed up. It requires focus and frequency to instill new patterns. You may have to back away from hard training and racing while specifically working on form improvements (as Mary Cain recently did). After these habits and motions have become ingrained, however, every run works to improve your skill, flexibility, strength and ability to maintain a more effective stride longer.
But even after the new skills have become habit, the environmental factors that predispose us to a perpetual sitting position are still all around. We all need to keep improving flexibility and strength. "There is really no magic in any one hip flexor stretch or one collection of glute-strengthening exercises versus another," McHenry says about his work with Mo Farah and others in the Oregon Project. "The magic is simply in the consistency in doing those things. You can't stretch your hip flexors every once in a while and do some glute-strengthening stuff on occasion and really expect any significant change to occur."
Many other elements combine to make a runner smooth and efficient. But, given their importance in the stride and the lifestyle factors that weaken how we use them, the hips are a great place to start. When we start to run taller, become more balanced and feel the float of an efficient hip drive, we are one step closer to running like the elites.
Exercise illustrations by Charlie Layton