With the rise in popularity of CrossFit also came the emergence of adventure or obstacle races. These competitions take your standard 5K or half marathon to the next level with lots of mud, man-made walls, barbed wire, and other obstacles to overcome.

While many of my clients (myself included!) are admittedly a bit intimidated by these types of races and competitions, more and more people are signing up for them across the country. These events offer opportunities to tap into physical and mental strength by overcoming extreme challenges. Some obstacles include monkey bars, two-story slides, crawls through mud and under barbed wire, and even a run through water while dodging dangling electrical wires.

When it comes to obstacle-based races, two companies have risen to the top in popularity: Tough Mudder and Spartan. Both of these popular events were founded in 2010. To date, more than five million people have participated in a Tough Mudder race, and Spartan claims to have attracted more than a million people worldwide in 2018 alone.

What’s the difference between Spartan and Tough Mudder?

The races are similar in that they hold hundreds of events across the world each year, which consist of a series of obstacles over a course of varying lengths. Both offer a series of different race options based on both time and distance, including a 5K option for more novice athletes and a popular 10-12 mile course with 20-25 obstacles. (They even offer 12- and 24-hour events for those really looking to push themselves to the extreme).

One of the main differences is that Tough Mudder is a team-based challenge, while Spartan races are more of an every-man-for-himself competition. Participants also say that Tough Mudder obstacles tend to be more creative and fun, while the Spartan obstacles are more physically challenging. You're also allowed to skip obstacles during a Tough Mudder race, while doing so during a Spartan race will cost you 30 burpees.

While they're accessible for everyone, proper training is key

“Spartan offers heats for all fitness levels and ages, from beginner to elite, along with races for kids as young as four years old,” Spartan CEO Joe De Sena told NBC News BETTER. And while the events are approachable for the whole family, he highly recommends following a proper training and nutrition plan leading up to the race and during the race itself.

These races are meant to be physically and mentally challenging throughout the entire course. They’re a mix of cardio and strength training and work your entire body. Therefore, the training needed to compete could potentially get you into the best shape of your life.

That being said, not everyone approaches them in a healthy way. Dr. Myles Spar, CMO of Vault Health, says that as a physician and men’s health expert who works with athletes, all too often he sees guys who thought they could just sign up for a race and pull through it without proper training. “Not only is that a recipe for injury, it also robs you of a true sense of having worked hard and achieved a stretch goal,” he says.

Injuries can happen — but most are preventable

Tough Mudder has gotten some negative press over the years as participants have been injured, and even died, as a result of some of the obstacles. There was a drowning death at a race in the last obstacle called Walk the Plank in 2013. In addition to the drowning death, 20 patients were sent to the hospital due to heart attacks, hypothermia, and a variety of orthopedic and head injuries. On another race weekend, 38 patients went to the hospital for broken bones, dislocations, head injuries, and other orthopedic injuries. Of course, Tough Mudder isn’t alone in this, deaths due to drowning are also reported in triathlon races, and marathons and other competitive events have their fair share of injured participants. Oftentimes the camaraderie and motivational atmosphere can push individuals to compete in these races without the proper physical training, and this can be compounded by pre-existing health issues.

While drastic injuries do occur, the most common are smaller — but pesky and painful — injuries that can knock you off your feet. In terms of potential injuries, Kevin Hanover, founder and head coach at HBodyLab LLC, who coaches endurance athletes, says that the most common injuries he sees deal with calf strains and lack in mobility. “Most endurance athletes neglect lateral movement and strengthening opposing muscle groups of those that are worked most often,” he explains.

I always emphasize four types of training to avoid injuries: cardio or endurance training, resistance or strength training, flexibility and core. Dr. Myles Spar

“Mostly I see knee and ankle sprains, even tears of the meniscus or cruciate ligaments of the knee,” adds Dr. Spar. “These can be largely prevented by proper warm-up and stretching. Stretching should be done especially after a workout or at least after a warm-up, when your muscles are warm and stretchable. I These last two are often ignored and hugely important when it comes to injury prevention. Being able to quickly react to changing levels of a course or obstacles (like in a Tough Mudder) requires you to be able to bend and quickly adjust your body position, otherwise you will snap a tendon or ligament. Such quick adjustments require core strength and overall flexibility.”

How to train for a Spartan or Tough Mudder race

The best way to prevent injury and ensure you finish an obstacle race injury-free is to train properly and ensure your body is prepared for the physical feat. Here are three key areas our experts say it's important to focus on:

1. Total-body conditioning

Spar says that this training includes much more than just cardio, endurance and strength exercises. “Don’t forget forms of conditioning including yoga, Pilates or even stretch classes. Also, planks! The athletes I train consistently do planks as they aid in strengthening the core and entire body. Do those planks, because they will keep you going without injury.”

Hanover says that Tough Mudder is the event that most athletes come to him seeking training for. He approaches the training very tactically. “There needs to be a solid foundation of mobility, aerobic capacity and absolute strength built before we train for the specific demands of the event," he says. "A healthy dose of resistance training and endurance work, including cycling and running first, then we can work on the body being able to absorb the stress that the event may present such as hanging and dropping from specific heights.” In terms of training time? He advises 6 to 8 months depending on the length of the race.

2. Upper body and grip strength

Andrew Samuels, coach at Mile High Run Club, who completed a Spartan Race, says it’s much more about preparing for the obstacles than the running. “There were short runs in between each obstacle, but the course was crowded so you couldn’t really pass people during the running anyway. It was lot of stuff that targeted back, forearm and hand strength like monkey bars, climbing sideways on a wall, rope climb and bag pulls,” he says.

De Sena explains that a lot of Spartan's obstacles require an overhead traverse — or pulling yourself up and forward (like the multi-rig, monkey bars, beater, etc.), plus obstacles like the log carry where you are traveling a distance carrying a weight (in this case a log). To successfully complete these, you will need a fair amount of upper-body strength as well as grip strength. A great way to train for these obstacles is by adding farmer carries to your workout. These improve pillar strength and really work on grip endurance and strength. Start simply by lifting two kettle bells or heavy dumbbells (one in each hand) and walking or running to work on balance. Additionally, adding horizontal and vertical pulling exercises is a must: pull-ups, dead-hangs, inverted rows, bent over rows, etc.

3. Plyometrics

Obstacles like the King of the Swingers, vertical cargo +, and stairway to Sparta all have one thing in common: they require an explosive jump. Training plyometrics in your workout is an absolute must — not to mention, as we age, we lose our power output at over double the rate of that which we lose strength. To prepare, De Sena recommends doing box jumps, bounding exercises, eccentric focused plyometric exercises (working on landing mechanics) and hurdle jumps.

To do a bounding exercise, you can start with the basics. Simply push off one foot to jump up, and then land on the opposite foot with a softly bent knee. You’re trying to leap up into the air as high as you can and as far forward as you can; like an exaggerated sprint except you’re going for height and control along with speed. Eccentric focused plyo exercises focus on the explosive movement of an exercise with moves like jump squats, jumping lunges, and clap push-ups. For example, during a clap push-up, you press down through the ground to explode out of a push-up as high as you can so that there’s enough time in the air to allow you to clap before coming back down and landing with bent elbows. You’re working hard to explode and then working equally hard to come down with a smooth landing.

How to come up with a training plan

Coming up with a training plan is key to having a successful race. As a personal trainer myself, I advise my clients to find an experienced trainer that will devise a training program specific to them and their race. If the cost of a trainer or gym is an issue, focusing on a variety of workouts can help prepare the body for these types of races. I recommend doing at least one full-body HIIT workout a week, one strength training workout, a bootcamp workout, and finally a kickboxing or plyometric workout to focus on agility. You can also check out the race websites for more training resources. Spartan offers free training plans for specific obstacles, as well as a 30-day race prep training plan for $39.99. Tough Mudder also offers free training guides, as well as a subscription video training program. But as always, be sure to check with your doctor before beginning any new fitness routine.

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