Marathons and triathlons used to be the exclusive domain of hard-core athletes. Today, more and more amateurs are signing up, lured by the promise of free training in exchange for raising money for good causes (see BW, Spring 2005, "Worthy Workouts"). Here's a breakdown of groups that specifically coach participants for endurance events.

Organization: Team in TrainingBenefits: The Leukemia & Lymphoma SocietyLocation: NationwideEvents: Marathons, half-marathons, cycling events, triathlonsContact: teamintraining.org

Organization: National AIDS MarathonBenefits: Local HIV/AIDS organizationsLocation: Chicago, Los Angeles, San Francisco, Washington, D.C.Events: Marathons, half-marathonsContact: aidsmarathon.com

Organization: Train to End StrokeBenefits: American Stroke Assn.Location: NationwideEvents: Marathons, half-marathonsContact: strokeassociation.org

Organization: Joints in MotionBenefits: Arthritis FoundationLocation: NationwideEvents: Marathons, half-marathons, hikesContact: arthritis.org

Organization: MS 150 Bike Tour, MS Challenge WalkBenefits: National Multiple Sclerosis SocietyLocation: Nationwide, but training varies by local chapterEvents: Cycling events, 50-mile walkContact: nationalmssociety.org