A new report suggests that American are some of the most unhealthy in the world.

FOX's Jeff Monosso reports:

A study published in the British Journal of Sports Medicine says that U.S. kids would come in near the back of the pack in a global race, ranking American kids 47th out of 50 countries in aerobic fitness.

Grant Tomkinson, associate professor at the University of North Dakota says socioeconomics plays a roll, but so does too much screen time.

Federal guidelines recommend 60-minutes a day of physical activity:

(Tomkinson) "Less than 20-percent of U.S. school age children achieve that daily guideline, so their failing. Put the screens down for a few minutes and try to snack on some exercise."

Tanzania, Iceland, Estonia, Norway and Japan came in the top five in the kids fitness study. Mexico came in last.

Jeff Monosso, FOX News.

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