My involvement in Obstacle Racing began in 2011 and has evolved in just about every way - the races I run, the fuel I use, my preferred gear, and my training strategy. Related to the training, despite the occasional Atlas Carry or log drag, the vast majority of obstacles remain about getting yourself up, over, through, or in some manner around a challenge. 
There is a strong focus on functional movements, flexibility, and adaptability. I have yet to see a bench press on the side of a mountain.
To that end, I have tailored my workouts primarily around body weight exercises. I will add weights to certain exercises to increase difficulty, but usually not more than 50 pounds, as I find I can create extremely challenging movements without a lot of plates. After all, our ancestors didn’t use them right?!
The biggest benefits to me are:
Relevance: As stated above, the act of moving your body through natural movements represents most obstacles in OCR. Getting over walls, crawling under wire, monkey bars, etc... all utilize your body as the primary weight you must navigate.
Injury prevention: The reduced stress you put on your joints and tendons for many people, myself included, lead to a much lower injury rate. There is not as much external force, unnatural weight bearing, and impact.
Stability control: Just as bench pressing a bar allows for greater strengthening of your stability muscles as compared to a machine press, body weight movements tap into a much wider collection of muscles as you move to more involved exercises. The pistol squat for example forces an incredible amount of lateral strength through your entire leg than can be accomplished by adding weight to your squat rack.
Flexibility: It may be obvious, but without the need for weights, you can exercise just about anywhere - Hotel rooms when you travel, your own living room, the side of a trail during a run, your office, etc.
A few of my favorite bodyweight exercises are:
Pistol Squat - Stand on one leg with the other extended straight out and start your squat, keeping the leg and your arms (for balance) straight in front of you. Go as far down as possible if you can’t reach the bottom, pause, and slowly and controlled stand up. Balance will be very hard as you begin so start slow.
L Pullups - Perform standard pullups but keep your legs straight in front of you at a 90 degree angle, using your core to lock the L. This will require much more body control and work every muscle from your legs up to your shoulders.
Semi planche pushups - This is a pushup, but you place your hands at your waist with your hands pointed outwards. Be careful to let your wrists adjust as it will stress them bit at first. From there perform your pushup, careful not to cheat and arch your back. The evolution here is to a planche pushup, in which you lift you whole body, feet included. Start with a one-footed semi planche to work up to that.
Medicine ball plank/pushups - First place 3 medium size medicine balls in a triangle, one at your feet and two under your shoulders. Place your hands on the two in front, find your stability, and then place your feet on the 3rd ball. With your core tight, plank for a minute, then do 5-20 pushups, then extend your left leg out off the ball and do 5-10 pushups, and repeat with your right leg off the ball. Focus on keeping the core tight and resist the urge to sag between the medicine balls. Finish with a plank until failure.
This is just a sampling; the sky is really the limit especially when you include cardio work along with it like burpee pullups or spiderman crunch crawls. Obviously everyone is different, but give these a try, especially if you often find yourself training outside a normal gym!
This is a guest post by Brian Lynch. Brian works in Wealth Management at UBS in Boston MA and has been involved in OCR since 2011. Recreation quickly turned to passion and then to obsession, and Brian now focuses his training on Ultra Distance OCR. Brian is a 2 time Worlds Toughest Mudder participant (finishing and completing 50 miles in 2012), a 2 time Spartan Ultra Beast finisher, and one of the 40 inaugural Fuego Y Agua Survival Run competitors. Brian's training focuses on body weight exercises for functional strength, high intensity circuit training for cardio and agility, and long distance trail running for endurance.
