Welcome to MBPost!  -
Anaerobic Effort.

Anaerobic Effort.

  Featured on the Front Page

Page Type: Article

Activities: Mountain


Page By: chaberton

Created/Edited: Oct 15, 2012 / Oct 15, 2012

Object ID: 285475

Hits: 2482 

Page Score: 74.01%  - 4 Votes 

Vote: Log in to vote



Know your physical limits!
Now in my fiftieth birthday (it lacks only one more year) and after a life of debauchery (Bacchus, Tobacco and Venus), I came to an awareness, i have to face the mountain and biking, not only with due more than ever, but also with a renewed respect for my body, its limitations, its potential.

Some small alarm bells, dizziness, muscle cramps and small (but many) pains, that occur the day after an excursion in the mountains, made me realize that my body is no longer that of a twenty year old and requires more care and attention.

With all this, I certainly do not say that I feel like Methuselah, but one thing is for sure, half a century of life takes its toll on joints, muscles and cardiovascular system.
So, to continue to do my favorite activity (as usual) in the mountains, enjoying myself like a madman, would rather try to better understand my limits, not to overcome them and have bad surprises.
<FONT COLOR=RED><i>Finis Terrae Cotii</i></FONT>.

Bioenergetic and biomechanical considerations.

Riding the mountain of the thunder. <FONT COLOR=BLUE>Part One</FONT>.
The style of biking can not disregard the following assumptions biomechanical and bioenergetic: 1) the strength of contraction is proportional to the cross-sectional area of the muscle, which, together with the different characteristics of muscle fibers, justifies the greater strength of resistance of the lower limbs with respect to the upper 2) the speed of muscle contraction is inversely proportional to the force developed and 3) the maximum strength is developed at an optimum length of the muscle; 4) the efforts static (isometric) are particularly onerous from the point of view of energy, as induce a state of temporary anaerobiosis.

May the force developed by a muscle is proportional to its transverse surface is common knowledge that informs much of the preparatory exercises for strength sports, such as, for example., Lifting weights. It can be
assumed that a muscle develops a force equivalent to an average of 50 N per cm ². The maximum muscle strength plays a dominant role in the progression of forms in the wall free climbing and more about the sports that the real mountain climbing. In this context it should consider the different behavior of the muscle tissue according to the type of fibers that constitute it. It is known, in fact, that the muscle fibers are divided into two main types:

lens, with a majority oxidative metabolism (type I), and rapid, with predominantly anaerobic metabolism (type II). The fibers of the slow type, oxidative, constitute the majority of the drive units of the antigravity muscles to function, that is intended to support the weight of the body and held vertically. These are the muscles that incur greater mountaineer to fix the position on the wall during the progression. These muscles, located in the back and in the lower limbs, being very resistant to fatigue allow the maintenance of the position for more long term.

Otherwise, the arm muscles are composed mostly of fast-type motor units. The strength that they can develop is great, but the rapid consumption of energy substrates to the work of the expensive anaerobic metabolism makes them very resistant to fatigue. It is therefore not possible to maintain for long periods of time the position on a wall with the body literally 'hung'. The relationship of inverse proportionality between the force and the speed of muscle contraction is of importance during the fast movements necessary to overcome the critical steps of , sometimes considerably exposed. In this case it may be useful to a previous countermovement of 'hunting' in order to store energy in elastic elements of type of muscle tissue, energy which is then returned during the bounce, a bit 'as happens in the race for preparation of athletes intent on stand out a jump.

Muscles are inserted on the bone segments of the skeleton, normally in such a way that their length, at rest, is optimal at the end of the development of force. For this length, in myofibrils fact is the maximum possibility of interaction between the heads of myosin and actin reactive sites, namely the two muscular structures that constitute the power generator at the base of muscle contraction. It follows that the climber must avoid to grip on footings that require an excessive stretching. The muscles may still be 'trained' to work with longer lengths of so-called training exercises by stretching or elongation.

Finally, the Biker must avoid taking positions or making efforts with isometric mode, acting, ie, against an infinite resistance. In this case muscle contraction, tetanus and type of protracted, initially and would prevent a disadvantage in the long run the necessary supply of oxygen by the circulation to the muscle which works. The blood vessels tributaries, in fact, would be compressed by the contracted muscles around them. In other words, this method of working leads rapidly in the muscle ischemic conditions, that is to place it in metabolic conditions of type anaerobico. Muscles draw the energy required for contraction by cleavage of the acid adenosintrifosforico (ATP), which must be renewed continuously.
This occurs thanks to the use, in very short times (<10 s) of phosphocreatine or, in time a bit 'longer (about 40 s) of the anaerobic glycolysis resulting in the production of lactic acid or, finally, also for very long times the complete oxidation of carbohydrates and lipids. The first two mechanisms are limited in time, since they cause a rapid depletion of muscle energy reserves and, for the anaerobic glycolysis, including acidification of the muscle tissue. This puts a time limit to the short supply, but that does not exist for the oxidative mechanism. The net mechanical work done of the Biker is proportional to the product of weight lifted for the difference.

The relationship between the mechanical work and the energy consumed, expressed in the same units of measurement, is the efficiency of the slope, in accordance with the laws of thermodynamics, is <1, a part of the energy being dispersed into heat. The climb takes place on a wall on uneven terrain, in a discontinuous and involves the activities of disparate muscle groups (arms in particular) are often used in static conditions, which leads to a yield of 0.08 to 0.1 (8 -10%), well below the optimum efficiency of muscle contraction (0.25 to 0.30).

The myoglobin.

Riding the mountain of the thunder. <FONT COLOR=RED>Part Two</FONT>.
In muscle is present, a substance, myoglobin, a pigment of red color. Myoglobin has a certain resemblance to hemoglobin, which also binds with oxygen. The task of myoglobin, however, is not to store oxygen. Rather,myoglobin increases the solubility of oxygen in the muscle tissue. This increase in solubility is used to broadcast as fast as the oxygen through the muscles and to increase the concentration of oxygen in the muscle cells.
The concentration of myoglobin is very high in the muscles aerobic or in those with slow contraction, in which are possible very high consumption of oxygen. Because of the high content of myoglobin, they assume a dark color.
On the contrary, the muscles anaerobic or those which are contracted rapidly have a content of myoglobin much lower and tend to be pale. The slow twitch muscles also receive an abundant blood supply that makes them darker than the fast twitch.

Lactic Acid.

<FONT COLOR=RED>The Jugment Day.</FONT>
The lactic acid or lactate is a byproduct of anaerobic lactic metabolism. It is a toxic compound to the cells, whose accumulation in the blood flow is correlated to the appearance of the so-called muscle fatigue.
The lactate is produced already starting from low exercise intensity; the red blood cells, for example, the continuously formed even in conditions of complete rest.
An adult male normally active produces about 120 grams of lactic acid per day; 40 g of these are produced from the tissues having an exclusively anaerobic metabolism (retina and red blood cells) the remainder from other
tissues (mainly muscle) depending on the actual availability of oxygen.
The human body has defense systems to protect themselves from lactic acid and can convert it back into glucose through the activity of the liver. The heart is instead able to metabolize the lactic acid to produce energy.
From these statements it can be deduced such as lactic acid, although toxic, is not a real waste product. Thanks to a series of enzymatic processes that substance may in fact be used for the resynthesis of intracellular glucose.

Recent studies point out that lactic acid is in reality only indirectly involved in increasing blood acidity. The main responsible for this phenomenon is the hydrogen ion H that during a physical exercise high intensity is released in large quantities for the increase of the hydrolysis of ATP.

At the same intensity of exercise, the amount of lactic acid produced is inversely proportional to the degree of training of the subject. This means that if an athlete and a sedentary run at the same speed, the latter produces much more lactic acid compared to the first and disposing with more difficulties.
During strenuous muscle work when the aerobic metabolism is no longer able to meet the increasing energy requirements, an accessory pathway is activated for the production of ATP called anaerobic mechanism lattacido.

This phenomenon while compensating in part the lack of oxygen increases the proportion of lactic acid produced which in turn exceeds the capacity of neutralization by the body. The result of this process is an abrupt
increase in the proportion of lactate in the blood which roughly corresponds to the frequency of the anaerobic threshold of the subject.
The blood concentration of lactate in the blood is usually of 1-2 mmol / L at rest but during strenuous exercise can reach and exceed 20mmol / L.
The anaerobic threshold, as measured by the blood concentration of lactic
acid, is made to coincide with the heart rate value for which in the course of an incremental exercise is reached the concentration of 4mmoli / L.
Lactic acid began to accumulate in the muscles and in the blood when the speed exceeds the speed of synthesis of disposal. Roughly, this condition is triggered when, during an intense exercise heart rate above 80% (for non-trained) and 90% (for more trained) of maximum heart rate.
Increasing tolerance to lactic acid.
The athletes involved in anaerobic lattacide disciplines (duration of stress between 30 and 200 seconds) are forced to compete in conditions of maximum production and accumulation of lactate. Their performance is then
related to the efficiency of the anaerobic metabolism of lactate and disposal systems in the blood, liver and muscle.
The purpose of the training targeted to the increase of these characteristics is to saturate the muscles of lactic acid in such a way that get used to work in conditions of strong acidity. At the same time this approach improves the effectiveness of the blood buffer systems (bicarbonate) to neutralize blood acidosis.
The athlete has two training techniques to achieve improved performance anaerobic lactic acid:
one based on continuous effort (20-25 minutes) to values of heart rate close to anaerobic threshold (± 2%)

A method based on the work at intervals: 2-6 in athletics repeated for 1-4 sets of 150-400 meters at race pace or faster interspersed with partial recovery between repetitions (45-90 seconds) between sets and complete (5-10 minutes).

Lactic acid is disposed in the space of 2 or 3 hours, and its quantity is halved every 15-30 minutes depending on training and the amount of lactic acid product.
Contrary to what is often claimed, lactic acid is responsible for muscle soreness felt the next day to a very intense workout. This pain is caused by muscles that originate micro-injuries inflammatory processes, and there is an increase of blood and lymph activities that increase the sensitivity in the muscles most stressed areas.
Lactic acid is a strong stimulus for the secretion of anabolic hormones such as GH and testosterone. This is why weight training exercises with high intensity, punctuated by pauses not too long, maximize the gain of muscle mass.

The 65% lactic acid product is converted into carbon dioxide in water, 20% is converted into glycogen, 10% protein and 5% in glucose.

Training at high altitudes.

I am thirsty!
Ten to fifteen years ago, a group of athletes from different villages of Kenya, Tanzania and Ethiopia located in high latitudes resulted winners in endurance events at the Olympics in Mexico City. Since Mexico City is located at 2000 meters above sea level, for a time it became customary to train athletes in endurance events to the high-altitude locations.
One of the consequences of hypoxia from altitude training in the muscles of new capillaries that allow blood to spread mainly by reducing the distance between the zones of diffusion. It also occurs an increase of the enzymes responsible for the reactions of aerobic metabolism, with the result of increasing the capture oxygen. Finally, the high-altitude hypoxia stimulates the production of red blood cells, thus increasing the number and enriching the blood hemoglobin in a few weeks. This increases the oxygen carrying capacity, but also produces an increased density of blood, resulting in reducing the frequency of heart rhythm. Sometimes the natives of the lands located at high altitudes have a disease (Monge's disease) due to which red blood cells constitute over 75% of the total volume of blood (the norm is 45%), so that the viscosity of blood increases by two times.
Several weeks of training at high altitudes can be competitive in the conduct of sporting athletes living at low altitude against athletes from high mountain areas. However, it is not entirely proven that a period of training at high altitudes may be an advantage for an athlete who must then compete at sea level. This probably occurs because both the oxygen consumption that the amount of work done at higher elevations are lower than normal. Since at high altitudes you can not program a high level of training, it is possible that this produces a slight effect of "deprivation", with the result of counter any increase in ability to carry oxygen.
Another explanation might be that training at high altitude reduces the buffering effect produced by bicarbonate in the blood. This, in turn, can make the athletes less able to counteract high concentrations of lactic acid which are produced during sports competitions. However, the normal content of bicarbonate of the blood and its buffer effect are usually restored in 24 hours, for which this explanation seems not to be correct.
Finally, the resistance capacity is often limited by two concomitant factors, namely, the reduced blood volume and the increase of its viscosity when the body tends to dehydrate due to excessive sweating .

Training at high altitude increases the concentration of red blood cells, the viscosity of the blood of athletes who train at high altitudes tends to rise and increasing more and more with the increase in sweating.

Calculation of anaerobic threshold.

Calculate the approximate value of heart rate corresponding to his anaerobic threshold is rather simple and fast. It is enough to subtract your age to 220 and multiply the result by 0.935. Let's see an example:

a person of 40 years will have a maximum heart rate equal to 220-40 = 180 bpm (beats per minute).

The frequency corresponding to the anaerobic threshold is equal to: 180 x 0.935 = 168 bpm.

This calculation is valid for a trained person - in which the buffer systems and the organic adaptation generally ensure the efficient removal of the lactic acid product - but for a sedentary the frequency of anaerobic threshold may be much lower and placed around the 70% of HRmax.


Always together!
With this article is not that I want to become your backpack a portable laboratory (blood gas analyzer and heart rate are always with me, especially during the escursions in the mountains with horses, thay are suffering terribly from exertional myoglobinuria and Tying Up).
But with a little more weight, you have the opportunity to gather important biometric data of your body.

When I reach the summit of a mountain in the Western Alps, there are two objects of my backpack that always arouse interest, my flask of brandy and heart rate (in order).

The use of heart rate in the high mountains, is a useful way to get your Aerobic Threshold and not exceed it.
As you read is about the 80-85% of your maximum heart rate. The heart rate monitors available today are sufficiently precise, small and not heavy (the thimble is really the minimum). A useful way to learn about their state of hydration is the hematocrit. Plus it raises your blood is more dense. Exist in the market of small appliances, and with a good degree of reliability, can provide an impressive amount of data on your metabolism.
Regarding the integration of minerals lost through sweating, I personally prefer not to use integrators, at most, in hot weather, when forming the whitish halo at the edge of the sweat, I just slowly suck one tablet of Enervit.
What seems clear is that our body needs the compensatory pauses, its mechanisms work fine (just do not abuse it). it is equally essential not to miss him ever to integrate water, is always the rule that if you drink when you are thirsty (it is late), you're already dehydrated.


Know your physical limits!I Clench my teeth!


No comments posted yet.