We thank you for the opportunity to respond to the letter by Drs. Pakzad and Safiri. We appreciate their interest in our paper but find their letter unwarranted. First, it is not the intent of all survival analyses to evaluate all-cause mortality as the outcome strictly for statistical power or sample size issues. As indicated by Pakzad and Safiri, survival-based analyses could fit hierarchical models if indeed there was an interest to evaluate numerous cause-specific outcomes, which was not of interest in our study. The second issue raised by Pakzad and Safiri is that we did not compute adjusted analyses to evaluate the “independent” association of muscle-strengthening activities on mortality. This appears to be an oversight by Pakzad and Safiri, as our analysis section indicates that we employed adjusted models to evaluate the independent association of muscle-strengthening activities on mortality. Lastly, Pakzad and Safiri indicated that we did not evaluate the proportional hazard assumption, and thus indicate that our findings may be incorrect or misleading. However, the second paragraph of our results section indicates that this proportional hazard assumption was not violated in our analyses.