When most people are on a budget, charitable donations are often the first expenditures to get axed. The Plus 3 Network, however, rewards athletic individuals by donating on their behalf to the charity of their choice.

Anyone can participate, whether it's you, me or Michael Phelps. All you do is sign up for a free account on the Plus 3 Network, choose a cause and start working out. You can enter your workout activities manually, but uploading them with a GPS-verified record yields three times the value that is assigned to manual entries.

The Plus 3 Network also helps workout fiends organize. Every user can choose to make their workout public or keep it private. This opens the door to community activities that are beneficial to both your body and your cause of choice.

According to the Plus 3 Network site, swimming yields the most donation money per mile at 20 cents. Walking will earn about 5 cents a mile, while road biking earns about 2 cents per mile.

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