Reading ComprehensionDifficulty: Hard

PT147 S2 P1 Q4 Explanation

Muscle Memory

A free, expert breakdown of this official LSAT Reading Comprehension question.

TopicsAuthor OpinionScience

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Passage

Passage A Muscle memory is a puzzling phenomenon. Most bodybuilders have experienced this phenomenon, yet virtually no discussions of it have appeared in scientific publications. Bodybuilders who start training again after a period of inactivity find that gaining muscle size seems easier the second time around—even if athletes observing muscle memory, some plausible explanation must exist.

One potential explanation of muscle memory involves the neurons (nerve cells) that stimulate your muscles, telling the muscle fibers to contract. It is well established that during weight lifting, only a small percentage of neurons for the working muscles are recruited. The more weight you lift, the more neurons are involved and you may think you’re starting from the same place, this greater strength would enable faster progress.

Then again, it’s also possible that the ease of retraining has nothing to do with your muscles: it could all be in your head. The first time you trained, you didn’t know how much you could lift. So you increased weight cautiously. When retraining, you already know you can handle increasing weight These more rapid weight increases produce quicker gains in strength and size.

Passage B Pumping up is easier for people who have been buff before, and now scientists think they know why— muscles retain one aspect of their wither from lack of use.

Because muscle cells are huge, more than one nucleus is needed for making the large amounts of the proteins that give muscles their strength. Previous research has demonstrated that with exercise, muscle cells get even bigger by merging with stem cells that are nested between them. The muscle cells incorporate the nuclei extra cell nuclei are killed by a cell death program called apoptosis.

In a recent study, researchers regularly stimulated the leg muscles of mice over a two-week period, during which time the muscle cells gained nuclei and increased in size. The researchers then let the muscles rest. As the muscles atrophied, the cells deflated to about 40 percent of their bulked-up size, but the muscle proteins again, providing a type of muscle memory at the cellular level.

What this question is testing

Author Opinion

Your task

Pin down exactly what the question asks about the passage — a detail, the author's view, the structure, or the main point — before looking at the choices.

Common trap

Answers that restate a true detail from the passage but don't answer the specific question being asked.

Winning move

Anticipate the answer in your own words from the passage, then find the choice that matches that prediction.

Reading along? Open the full official question in LawHub — we show a fragment here and keep the reasoning in our own words.

The question
4.

It can be inferred from the passages that the author of

Answer choices

  1. Unsupported Disagree Position: Similar Certainty3% picked this

    is more certain than the author of passage B about the existence

    Both authors seem about the same, in terms of being convinced. The opening paragraph of Passage A ends with "with so many athletes observing muscle memory, some plausible explanation must exist". Meanwhile, the opening of passage B is saying, "Pumping up is easier for people who have been buff before". So both authors believe that muscle memory is a real phenomenon.

  2. Too Speculative19% picked this

    probably agrees with the author of passage B about the explanation

    Passage A spitballs a couple explanations for muscle memory (more muscle fibers are recruited / it's all in your head), neither of which are the same as the explanation pitched in Passage B (muscle cells retain a 2nd nucleus). Even though I found Passage B's explanation to be pretty compelling, I have no support that the author of Passage A would. In fact, I'm not even sure Passage A has ever heard of the explanation in Passage B.

  3. Correct67% picked this

    was probably not aware of the scientific research that is described

    Why this is right

    This may also feel speculative, but we have some text to point to support our case: The 2nd sentence of A says: virtually no discussions of it have appeared in scientific publications The 1st sentence of B says: now scientists think they know why And passage B's 3rd paragraph talks about a recent study on muscle memory. There's also common sense support for this answer. If the author of Passage A were aware of this passage and aware of the double-nuclei basis for muscle memory, then she would have mentioned it as she was discussing possible explanations for the existence of muscle memory.

    Skill tested: Author Opinion · how this choice captures the passage's function is the move to repeat next time.

  4. Unsupported Disagree Position6% picked this

    probably disagrees with the author of passage B about how muscle cells' nuclei

    We have no support that Passage A has any awareness at all of this bonus-nucleus explanation for muscle memory. She doesn't bring it up, and doesn't even think that any scientific studies have been published on it.

  5. Unsupported: skeptical of other species6% picked this

    tends to be more skeptical than the author of passage B about conclusions drawn about one species on the basis

    This answer is asking us to think, "Since passage A didn't bring up the bonus-nuclei explanation from the mouse experiment, that author must not think it's a plausible explanation yet because she doesn't trust explanations for human physiology that are predicated on experiments about mouse physiology." That would be a ton of speculating on our parts. It doesn't seem like passage A is even aware of this experiment (that passage may have been written before the second one).

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