Crossfit workouts are brutal but they are a sure fire way to test your speed, strength and endurance. Want to see what your made of? Here are 5 of the hardest crossfit WOD's that are sure to leave you gasping for air and wondering why you entered the gym...oh, and have you coming back the next day.

1.  "The Fran":

Three rounds, 21-15-9 reps of 95-pound barbell thrusters and pull-ups, all done for time.

2.  "The Filthy 50":

For time:
50 Box jump, 24 inch box
50 Jumping pull-ups
50 Kettlebell swings, 1 pood
Walking Lunge, 50 steps
50 Knees to elbows
50 Push press, 45 pounds
50 Back extensions
50 Wall ball shots, 20 pound ball
50 Burpees
50 Double unders

3.  "The Seven":

Seven rounds for time of:
7 Handstand push-ups
135 pound Thruster, 7 reps
7 Knees to elbows
245 pound Deadlift, 7 reps
7 Burpees
7 Kettlebell swings, 2 pood
7 Pull-ups

4.  "The Murph":

For time:
1 mile Run
100 Pull-ups
200 Push-ups
300 Squats
1 mile Run

5.  "The Ryan":

Five rounds for time of:
7 Muscle-ups
21 Burpees

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