Questão de Natural Sciences and their Technologies #019e354b
As fibras musculares esqueléticas não são todas iguais. As fibras lentas, também conhecidas como fibras vermelhas, apresentam muitas mitocôndrias e são bem supridas por vasos sanguíneos. Já as fibras rápidas, ou fibras brancas, apresentam poucas mitocôndrias e recebem menor suprimento sanguíneo. Dessa forma, a distribuição das fibras nos músculos esqueléticos do corpo auxilia de forma diferenciada no desempenho físico de um atleta.
An athlete who dreams of competing in the Olympic Games and has a higher proportion of white muscle fibers than red muscle fibers would have more advantages in performing the following event:
Triathlon.
High jump.
Race walking.
Open water swimming.
Road cycling.
Explicação Oficial / Explicações da Comunidade
Analysis of Muscle Fiber Types and Athletic Performance
The correct answer is option A. B) High jump.
1. Characteristics of Muscle Fibers
The text presents two types of muscle fibers with distinct specializations for energy production:
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Slow-twitch (Red) Fibers: * Features: Many mitochondria and a high blood supply (rich in oxygen). * Metabolism: They are adapted for aerobic cellular respirationThis process is highly efficient in producing ATP (energy), but it is slower. * Function: Ideal for activities of long lasting and durableFor example, in marathons, they are resistant to fatigue.
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Fast Fibers (White): * Features: Few mitochondria and low blood supply (poor in oxygen). * Metabolism: They are adapted for **anaerobic respiration (lactic fermentation)**This process produces ATP very quickly, but inefficiently, and generates lactic acid, which leads to fatigue in a short time. * Function: Ideal for activities of short duration, high intensity, strength and explosiveness, such as 100-meter sprints and weightlifting.
2. Athlete Profile and Race Analysis
The athlete in question has a higher proportion of white (fast) fibersThis means that their physical profile is advantageous for sports that require peak power and strength in a very short period of time.
THE High jump This is the perfect example of this type of activity. It consists of an approach run followed by a single explosive, maximum-power movement to propel the body vertically. The duration of the main effort is only a fraction of a second, depending entirely on the ability of the muscles to contract quickly and strongly.
3. Evaluation of Other Tests
The other options represent evidence of resistance (or endurance), which require continuous effort over a long period:
- A) Triathlon: It combines swimming, cycling, and long-distance running. * C) Race walking: Long-distance race with specific walking rules. * D) Open water swimming: Swimming in open water for several kilometers. * E) Road cycling: Long-distance and endurance race.
All of these modalities depend predominantly on aerobic metabolism and, therefore, would be more advantageous for athletes with a higher proportion of slow (red) fibers.
4. Conclusion
An athlete with a predominance of fast-twitch (white) muscle fibers has a competitive advantage in events that require explosive muscle power and short bursts of strength. Among the options presented, the... High jump This is the test that best fits that profile.