Medical researcher: Scientists compared a large group of joggers who

Question

Medical researcher: Scientists compared a large group of joggers who habitually stretch before jogging to an equal number of joggers who do not stretch before jogging. Both groups of joggers incurred roughly the same number of injuries. This indicates that stretching before jogging does not help to prevent injuries.

Which one of the following, if true, would most weaken the medical researcher’s argument?

(A) For both groups of joggers compared by the scientists, the rate of jogging injuries during the study was lower than the overall rate of jogging injuries.
(B) Among the joggers in the groups compared by the scientists, many of those previously injured while jogging experienced difficulty in their efforts to perform stretches.
(C) Most jogging injuries result from falls, collisions, and other mishaps on which the flexibility resulting from stretching would have little if any effect.
(D) The more prone a jogger is to jogging injuries, the more likely he or she is to develop the habit of performing stretches before jogging.
(E) Studies have found that, for certain forms of exercise, stretching beforehand can reduce the severity of injuries resulting from that exercise.

Source:LSAT

ShashankDave · Accepted Answer

Let's name the groups - Group A(Stretchers) and Group B(Non-Strechers).

Only (D) weakens the arguement.

This option clearly states that people who are more prone to injuries develop a habit of stretching. So Group A, the members of which were more likely to suffer injuries actually suffered the same number number of injuries compared to that of Group B, who don't stretch because they are not as prone to injuries as the members of Group A. 
This clearly means that members of Group A actually saved themselves from atleast some injuries.

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mbain20 · Answer

Conclusion :
 stretching before jogging does not help to prevent injuries.

So we should look for an answer option that would undermine this conclusion.

Option Analysis:
(A) For both groups of joggers compared by the scientists, the rate of jogging injuries during the study was lower than the overall rate of jogging injuries.
 "Rate of jogging injuries" is not the concern and also it does not help explain why stretching would rather help prevent injuries.

(B) Among the joggers in the groups compared by the scientists, many of those previously injured while jogging experienced difficulty in their efforts to perform stretches.
 Out of Scope

(C) Most jogging injuries result from falls, collisions, and other mishaps on which the flexibility resulting from stretching would have little if any effect.
 "Flexibility" is not talked about.

(D) The more prone a jogger is to jogging injuries, the more likely he or she is to develop the habit of performing stretches before jogging.
 This hints that stretching does have some positive effect. Hold on to it.

(E) Studies have found that, for certain forms of exercise, stretching beforehand can reduce the severity of injuries resulting from that exercise.
 I dont know if jogging would be classified under "certain" exercises.

Answer Option - D

aaditya005 · Answer

I picked E because of two reasons:
1) It adds another factor i.e. severity of the injuries, that could vary and people who exercise could lessen the severity of injuries by exercising.
2) Since outside information is allowed, we could categorise jogging in certain exercises.

Can anyone clarify me on this one?

Posted from my mobile device

nightblade354 · Answer

Because (E) isn't about jogging itself. We want to weaken the claim that stretching doesn't help us during jogging. The answer says "some forms". What does this mean? Is jogging a part of this? We have no idea. You cannot assume that jogging is a part of this group because you could make the equally valid claim that it isn't. You cannot make assumptions like this to validate your answer.

Rukia · Answer

Why is C wrong? If most of the jogging injuries are not caused by stretching then the author cannot make that statement about stretching not being useful.

princeann · Answer

C is actually strengthen the argument. It implies that stretching has little to do with the kind of injuries, such as falls, collisions .. 
Therefore, if the flexibility warm up doesn't help, it echoes the medical researcher argument that the stretch doesn't help to reduce injuries.

unraveled · Answer

Medical researcher: Scientists compared a large group of joggers who habitually stretch before jogging to an equal number of joggers who do not stretch before jogging.  Both groups of joggers incurred roughly the same number of injuries. This indicates  that stretching before jogging does not help to prevent injuries.

Which one of the following, if true, would most weaken the medical researcher’s argument?

(A) For both groups of joggers compared by the scientists, the  rate of jogging injuries during the study was lower than  the overall rate of jogging injuries. - WRONG. Numbers and rate are non-comparable. 
(B) Among the joggers in the groups compared by the scientists,  many of those  previously injured  while jogging experienced difficulty in their efforts to perform stretches . - WRONG. The passage core still remains intact as these people must have been segregated as suggested.
(C) Most jogging injuries result from falls, collisions, and other mishaps on which the flexibility resulting from stretching would have  little if any effect . - WRONG. Strengthens actually. 
(D) The more prone a jogger is to jogging injuries, the more likely he or she is to  develop the habit of performing stretches before jogging . - CORRECT.
(E) Studies have found that,  for certain forms of exercise , stretching beforehand can reduce the  severity of injuries  resulting from that exercise. - WRONG. For two red-text parts

Sadly, D is the answer but I don't think it has merit, especially the highlighted text. Developing habit is concerned with jogger not the study. 
It would have been better had the choice given some light to how the two compared to each other at the start of the study and how it was at the end of it.
True weakener would have been the one if it had elaborated that the stretching joggers were more compared to non-stretching joggers.

Answer D.

ironman_97 · Answer

Complete Question Explanation

https://forum.powerscore.com/viewtopic.php?t=2152

Weaken—CE. The correct answer choice is (D)

It is based on the results of a study involving a large number of joggers, split into equal groups of stretchers and non-stretchers. During the study the same number of joggers from each group experienced jogging related injuries. Thus, the researcher concluded that stretching prior to jogging did not actually help to prevent injuries. To weaken this conclusion, we will want to attack the study. The groups are the same size, and the structure of the study does not provide a motivation for participants to report false data. While this question may be a bit difficult to prephrase, we are still able to recognize that the correct answer choice will likely be related to the casual relationship described above.

Answer choice (A): This answer choice is incorrect because we do not have information about the overall rate of stretching in the general jogging public. Since the conclusion focuses on a causal relationship between stretching and avoiding jogging injuries, without information regarding the frequency of stretching in the general jogging public we cannot determine how this answer choice would impact the argument.

Answer choice (B): This answer choice looks tempting, because it seems to suggest that the injuries cause the difficulty with stretching. However, the conclusion does not distinguish between those who had difficulty with stretching and those who did not. It doesn’t matter if those with prior injuries struggled to stretch as long as they actually did stretch.

Answer choice (C): This answer choice actually strengthens the argument. It supports the idea that stretching does not help prevent injuries by stating that most jogging injuries are caused by factors that stretching would not address.

Answer choice (D): This is the correct answer choice. Answer choice (D) suggests that joggers who are particularly prone to injuries are more likely to stretch before jogging. Given that both groups of joggers incurred the same number of injuries, it is reasonable to suspect that stretching can lower the otherwise high risk of jogging injuries among the people who stretch, so that both groups end up with the same number of injuries. This would corroborate the theory that stretching lowers the risk of injury, and weaken the conclusion of the argument.

Answer choice (E): This answer choice is incorrect as the stimulus does not differentiate between the severity of the injuries sustained by the joggers. The study only counted injuries versus non-injuries. Therefore, the fact that stretching can reduce the severity of injuries does not impact the causal argument relating the behavior of stretching to the occurrence of any injury.

VerbalBot · Answer

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Medical researcher: Scientists compared a large group of joggers who

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