Staying in shape can be challenging when you lack motivation or encouragement. Many people rely on online workout sites to keep track of fitness, find workout routines, and to get excited about getting in shape. According to the United States Department of Agriculture, adults require at least 2 hours and 30 minutes of moderate aerobic physical exercise a week, or 1 hour and 15 minutes of intense aerobic exercise. Use the wealth of knowledge found online to your advantage by checking out these excellent workout resources:

Fitness.com
Fitness.com provides a library of health and fitness tools for adults of all ages and skill levels. The site offers a plethora of free tools and information, as well as a portal to additional fee-based services in which you can subscribe. Find hundreds of exercise routines, articles, recipes, and interviews with body builders, fitness models, and more. The BMI and BMR Calculators, and Fit-o-Meter are designed to test your overall fitness and measure your weight loss. Fitness.com also offers free forums where you can find support for weight loss, training, and bodybuilding.

FITera.com
FITera.com, or Fast Track to Fat Loss, has made incredible strides in the world of online fitness programs. Founders of the site include a personal trainer, weight management specialist, A.C.E. coach, and nutritionist. For a fee, FITera.com offers numerous weight loss programs and tools, including a DVD series, meal planner, recipe book, as well as one-on-one A.C.E. coaching and accountability services. FITera.com also holds events for members, and has an incredibly supportive community.

RunKeeper.com
RunKeeper.com is the ultimate way to track your workouts and make exercising fun. Sign up with Facebook to gain instant access to RunKeeper, or get the app for free on your iPhone, iPad, or Android device. Easily monitor your runs and keep track of your exercise, as you can review your speed, distance, and progress over time, and customize your workouts as your strength and endurance grows. RunKeeper.com combines fitness with social media for the best of both worlds. Share your latest activities and progress with friends and family on Facebook and Twitter to boost your motivation.

GaiamTV.com
GaiamTV.com allows you to stream thousands of inspirational videos, original interviews, and fitness and yoga tutorials at the click of a button. This 100 percent ad-free website provides information on staying healthy through exercise and proper nutrition, as well as how to promote self-healing through mediation, personal development and other types of spiritual growth. When you sign up, you’ll receive free access to Gaiam TV for 10 days, and then it’s just $9.95 a month afterwards for unlimited access to original programming, inspirational content, and exercise classes. For additional information on cardio workouts or other streaming media, experience Gaiam TV for yourself.

Traineo.com
Traineo.com is a supportive weight loss community where online users can share user-submitted workout routines and provide each with other with motivation. Interact with other people who share the same or similar goals, and get inspired to get fit. Traineo.com also provides a plethora of information and advice, including motivation tips, diet plans, healthy recipes and snack ideas, and a before and after gallery of weight loss successes. This free weight loss application also provides diet and exercise tracking tools to monitor your progress along the way.