If you're dealing with just 1 predictor variable, you can use the correlation module in CMA (either inputting r directly or computing r from the p value and sample size). If the models have more than 1 predictor, you should be careful. Beta values from these models aren't necessarily comparable unless they all have the same predictors.

Hi Gregory, The regression will be looking at a Rating of perceived exertion (dependent variable) vs one independent variable, such as heart rate, blood pressure or exercise intensity 

I agree with Tim's answer.