Please rate my analysis of argument

ESSAY QUESTION:
The following appeared in a print advertisement for a dietary supplement:

“According to a recent study, professional bodybuilders who used Train & Gain, a new protein supplement, over the course of three months experienced an increase in measured strength of up to 20%. Since Train & Gain is now available without prescription at all major pharmacies, superior results are no longer limited to professional athletes. Try Train & Gain today and you too can boost your strength and achieve professional-level performance in just a few months.”

Discuss how well reasoned you find this argument. Point out flaws in the argument's logic and analyze the argument's underlying assumptions. In addition, evaluate how supporting evidence is used and what evidence might counter the argument's conclusion. You may also discuss what additional evidence could be used to strengthen the argument or what changes would make the argument more logically sound.

YOUR RESPONSE:
The argument presented here discusses the results of a study conducted on professional bodybuilders who gained strength on consuming Train and Gain protein supplement for three months. It then concludes by mentioning that any one who consumes this protein supplement can achieve such physical strength. Also, since it is easily available without prescription, it can easily by bought from pharmacies by anyone. Although, the argument does have some merit, it has certain flaws and it is based on some assumptions that undermine its validity.

First, the argument basis its conclusion on the assumption that the protein supplement that worked well for professional bodybuilders will also work similarly for anyone who consumes it. Although, this might be true for Train and Gain, author has failed to mention any such co-relation. Therefore, if certain study shows that protein supplements are only suitable for people who regularly do workouts, this argument will be substantially weakened. However, if the author can support this argument with a study conducted on common man, the argument would be strengthened.

Second, the argument assumes that the the only cause of increase in the strength of professional bodybuilders was this Train and Gain supplement. For example, it is possible that these professional bodybuilders were also under strict diets and were regularly doing workouts, or it is possible that they were also consuming some other protein supplements or steroids. The author should have mentioned the details of activities that these bodybuilders did and the diet consumed in those three months to bolster his or her argument.

Finally, although the argument mentions that the Train and Gain supplement is now available without prescription at pharmacies, it does not guide anyone about the consumption details or the amount prescribed with this protein supplement.

In conclusion, while the argument is supported by a study of the consumers of a protein supplement, it fails to successfully conclude that this protein supplement can boost the strength of anyone who consumes it.


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My analysis - minor grammatical errors with one typo - para 3 - assumes "the" repeated twice
Conclusion is not strong and clear.

I think rating would be around 4 for this. But asking from experts.