HMS, BM EQ-Bank 755 MC

During a 100-metre sprint, an athlete primarily uses which energy system and fuel source in the first 2 seconds?

ATP-PCr system using phosphocreatine
Glycolytic system using glucose
Aerobic system using carbohydrates
Aerobic system using fats

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\(A\)

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A is correct:
- In the first 2 seconds of a 100-metre sprint, the body relies on the ATP-PCr system.
- This system uses phosphocreatine as its fuel source to rapidly generate ATP for the explosive muscular contraction needed at the start of the sprint.

Other Options:

B is incorrect: The glycolytic system becomes predominant after approximately 10 seconds once PCr supplies begin to deplete.
C is incorrect: The aerobic system using carbohydrates is not the predominant energy system during the initial explosive phase of a sprint.
D is incorrect: The aerobic system using fats is used primarily during longer duration, lower intensity activities, not the explosive start of a sprint.