controlling sound with MAX MSP

Hi, I am creating music using the software ‘reason’. The music has about 6 separate tracks/layers, which together comprise the soundtrack for an installation. I want to find a way to turn off and on these tracks based on movement from participants. Is there an esay way of doing this with MAX MSP? Is there a particular object I should be looking at or is there some other applciation that I need to buy?

Thanks in advance!