Question

Creators of the Shake Weight, a moving dumbbell, claim that their product can produce "incredible strength!" Which of the additional information below would provide the strongest evidence supporting the effectiveness of the Shake Weight for increasing muscle strength?
Question 5 options:

Survey data indicates that on average, users of the Shake Weight report working out with the product 6 days per week, whereas users of standard dumbbells report working out 3 days per week.

Compared to a resting state, users of the Shake Weight had a 300% increase in blood flow to their muscles when using the product.

Survey data indicates that users of the Shake Weight reported significantly greater muscle tone compared to users of standard dumbbells.

Compared to users of standard dumbbells, users of the Shake Weight were able to lift weights that were significantly heavier at the end of an 8-week trial.

Answer 1

The option that provides the strongest evidence supporting the effectiveness of the Shake Weight for increasing muscle strength is:

**"Compared to users of standard dumbbells, users of the Shake Weight were able to lift weights that were significantly heavier at the end of an 8-week trial."**

This statement indicates a direct comparison of performance outcome (lifting heavier weights) between two groups over the same timeframe, suggesting that the Shake Weight may indeed be more effective than standard dumbbells for increasing muscle strength.