The Lizard of Oz
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RE: Don't Work Out As Hard In The Cold Months
Vaun, there are many studies demonstrating that muscle performance degrades with lower temperatures. Cold muscles behave similarly to fatigued muscles. I thought this was obvious enough, but if you want links, have at it:
http://www.ncbi.nlm.nih.gov/pubmed/52536...t=Abstract
Quote:Acta Physiol Scand. 1979 Sep;107(1):33-7.
Influence of muscle temperature on maximal muscle strength and power output in human skeletal muscles.
Bergh U, Ekblom B.
Abstract
The influence of muscle temperature on maximal muscle strength, power output, jumping, and sprinting performance was evaluated in four male subjects. In one of the subjects the electromyogram (EMG) was recorded from M. vastus lateralis, M. biceps femoris, and M. semitendinosus. Tm ranged from 30.0 degrees C to 39 degrees C. Maximal dynamic strength, power output, jumping, and sprinting performance were positively related to Tm. The changes were in the same order of magnitude for all these parameters (4-6% x degrees C-1) Maximal isometric strength decreased by 2% x degrees C-1 with decreasing Tm. The force-velocity relationship was shifted to the left at subnormal Tm. Thus in short term exercises, such as jumping and sprinting, performance is reduced at low Tm and enhanced at Tm above normal, primarily as a result of a variation in maximal dynamic strength.
http://jap.physiology.org/content/73/6/2457
Quote:Muscle temperature, contractile speed, and motoneuron firing rates during human voluntary contractions
B. Bigland-Ritchie , C. K. Thomas , C. L. Rice , J. V. Howarth , J. J. Woods
Journal of Applied PhysiologyPublished 1 December 1992Vol. 73no. 6, 2457-2461
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Abstract
A study was made of motoneuron firing rates and mechanical contractile parameters during maximum voluntary contraction of human hand muscles. A comparison of muscles that had been fatigued after a 60-s maximum voluntary contraction (MVC) with muscles that were cooled by approximately 5 degrees C showed that the contractile properties, in particular the rates of contraction and relaxation, were similarly affected in both conditions.
http://jap.physiology.org/content/92/1/354
Quote:Combined effect of repetitive work and cold on muscle function and fatigue
Juha Oksa , Michel B. Ducharme , Hannu Rintamäki
Journal of Applied PhysiologyPublished 1 January 2002Vol. 92no. 1, 354-361
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Abstract
This study compared the effect of repetitive work in thermoneutral and cold conditions on forearm muscle electromyogram (EMG) and fatigue. We hypothesize that cold and repetitive work together cause higher EMG activity and fatigue than repetitive work only, thus creating a higher risk for overuse injuries. Eight men performed six 20-min work bouts at 25°C (W-25) and at 5°C while exposed to systemic (C-5) and local cooling (LC-5). The work was wrist flexion-extension exercise at 10% maximal voluntary contraction. The EMG activity of the forearm flexors and extensors was higher during C-5 (31 and 30%, respectively) and LC-5 (25 and 28%, respectively) than during W-25 (P < 0.05). On the basis of fatigue index (calculated from changes in maximal flexor force and flexor EMG activity), the fatigue in the forearm flexors at the end of W-25 was 15%. The corresponding values at the end of C-5 and LC-5 were 37% (P < 0.05 in relation to W-25) and 20%, respectively. Thus repetitive work in the cold causes higher EMG activity and fatigue than repetitive work in thermoneutral conditions.
Here is a reasonable layman's explanation:
http://www.mythoracicpark.com/articles/1...rticle.htm
Quote:Tis the season, the aches and pains of winter.
By
Dr. Thomas Patavino D.C., MS, F.I.A.M.A.
It's the most wonderful time of the year. The Holidays are upon us and everyone is gearing up for the festive season. Time to pull out the mistletoe, trim the trees and prepare for Santa. Most of us can still find the spirit of the season, although it has changed dramatically since we were kids. The excitement and anticipation sometimes get lost in all the mayhem of the holidays. Although some seem to skate through winter stress free, the majority of us will feel some type of stress throughout the winter months. The cold weather, last minute holiday shopping, crowds at the malls, and the most dreaded of all….bills.
Winter seems to be the season we feel the most aches and pains. The cold weather decreases blood flow to the muscles, so they instantly tighten up with the chill of the blustery wind. Those tightened muscles become susceptible to injury. For starters, a tight, cold muscle shortens its length. This reduces our range of motion. Normal motions like walking up the stairs or reaching overhead are now much more difficult and noticeable to perform in the cold weather. It doesn't take a lot of motion or weight to injure a shortened cold muscle. Tying a shoe or picking up a purse or bag of groceries can strain a muscle.
A strained muscle, or what we commonly call a “pulled muscle” occurs when a shortened muscle is lengthened beyond its comfort zone. This is usually caused by an activity such as picking up an object, falling or slipping. When this occurs, some of the tiny muscle fibers are torn and ligaments and tendons are stretched. A variety of symptoms appear with this type of injury. Pain is probably the most noticeable. Those tiny tears in the muscle lead to inflammation, swelling, redness and the stimulation of pain receptors. Muscle spasm is also very common with sprain/strain injuries. Involuntary twitching and contractions occur. Sometimes the spasm can be so powerful, the muscle shortens to the point where it won't relax. A good example of this is when the back muscles lock up on someone and they cannot straighten up. Most of us have known someone who has had “their back go out” and have been incapacitated as a result. Although the back is a common area for strain and spasm, it can occur in any muscle that is overused or misused with activity.
Stress also takes its toll on our bodies. The body acts like a sponge when it comes to stress. We know we aren't supposed to keep things bottled up inside because stress harms the body. It puts strain on the heart, raises blood pressure and is linked to gastrointestinal problems. Without question, winter is probably the most stressful season of the year. Besides being influenced by the cold, muscles are also affected a great deal by stress. Those tiny little muscle fibers get tangled into knots when mental, chemical and physical stress show their ugly faces. Sometimes we don't even realize that we have stress in our lives and are muscles form those knots called trigger points. Trigger points are best described as a knot in the muscle that usually refers pain to other parts of the body. Common examples are knots in the upper shoulder area that cause tension head aches or pain that travels down the arm into the hands.
As stated, strained muscles and trigger points can occur with very little activity due to the impact of the cold weather. If it doesn't take a lot to aggravate the muscles, you can imagine the impact of shoveling snow or slipping on the ice. These are two of the more common culprits that lead to winter injuries. It is natural to feel some soreness after doing activity like shoveling since we don't use those muscles day in and day out. Slipping on the ice, with or without falling, can stretch and strain muscles causing muscle pain and inflammation.
How do we know what is normal soreness versus an injury that should seek treatment? I like to use the 3-day rule. Typically after a large amount of activity, the body should recover in 2 to 3 days. If the pain and soreness goes beyond that, chances are you injured the muscle and you should seek treatment to facilitate the healing process and avoid creating a chronic condition down the road. Typical sprain or strained muscle injuries can take 6 to 8 weeks to heal on average. This can be more or less in some cases, with better results occurring in those who take appropriate measures to ensure proper healing. Trigger points typically respond in 3 to 5 treatments. Restoring proper blood flow to the damaged muscle area is essential to alleviate referred pain. There are a variety of treatment options available and you should consult your health care professional to decide the best course of action.
It is impossible to predict what the winter may bring. Stress, cold and snow are inevitable forces that will undoubtedly enter our lives over the next few months. Dressing in layers will help keep those muscles warm to reduce the risk of injury. Bending at the knees and pushing snow instead of lifting or throwing it will reduce pressure placed on the low back. Sand, salt and kitty litter sprinkled on icy steps and walkways are suggested to decrease the chances of slip and fall injuries. Getting your Christmas shopping done early or buying through catalogs and online reduces holiday stress. In addition, one person should bare the burden of all the preparations involved with holiday gatherings. There is strength in numbers and this will reduce stress and anxiety. Although, one cannot guarantee a smooth sleigh ride through the winter, these suggestions may reduce seasonal aches and pains. Have a happy, safe and healthy holiday.
Again, I thought this stuff was obvious. But maybe not.
As far as lower vitamin D at wintertime, the literature is overwhelming so I'll leave that as an exercise for the reader.
same old shit, sixes and sevens Shaft...
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