When first tackling the world of training, gym bunnies and climbers alike undergo a gradual process of physical and muscular development. The first step is a lot of pushing and pulling; working the concentric phase of a movement. Slowly, as we move on to new techniques and theories, we adopt eccentric training, like negative pull ups and slow controlled squats, which appear to give us new gains and an education in how our muscles work. The last step is isometric contractions; certainly less glamorous than the previous two and definitely overlooked by many trainers. Isometric training may be old news to you, or the extra kick you need for your sessions. Either way, knowledge is power!
What is an isometric contraction?
The muscle works in 3 ways:
- Concentric: the shortening of a muscle while tensed
- Eccentric: the lengthening of a muscle while tensed
- Isometric: the tensing of a muscle while not changing length
Isometric contraction has been used in bodybuilding, powerlifting, and Olympic lifting for some time. The effect it has on increasing strength is well documented. In the 1950s researchers, Hettinger and Muller, found a single daily effort of two-thirds of a person’s maximum effort exerted for six seconds at a time for ten weeks increased strength by about 5% per week.
A rock climber’s fingers become strong through repetitive isometric contraction.
The benefits of training the isometric phase are not so obvious, but this contraction is great for building and maintaining strength, as well as rehabilitation and strength through a movement. The latter may seem out of character for something that does not involve movement, but if you break down the movement on a route into 3 sections you have:
- (concentric) pushing, pulling, cranking
- (eccentric) landing move, slowing movement, controlling
- (isometric) holding position, sticking movement, muscle preparation.
This isometric phase in the movement may only be for a split second, but it is integral to the climb.
Why use isometric training?
Variety is key to getting the gains that you want. Repeating training plans, rep ranges, and movement patterns encourages staleness, so including a curve ball like isometrics will promote results.
For climbers, it is natural to be surrounded by moments of isometric contraction, not just in mid-movement as discussed before, but also in cases of slab climbing, when an almost sloth-like quality is needed.
Isometric contraction can be induced by tensing in a position or applying pressure to an immovable object. This is the key principle behind finger strength training. Pinches and hangboards are both immovable objects that we squeeze and crimp on. A rock climber’s fingers become strong through repetitive isometric contraction.
Related: The Best Hangboard Workout … Period
Including isometric contractions in a climbing drill is a great way to build specific strength by emphasizing the isometric part of the movement. Try this:
- Choose a wall with a decent overhang (i.e. 45 degrees)
- Make a move on the wall and once established, hold and tense for 3-5 seconds
- Continue on to the second move, then repeat when move is landed
Training the isometric phase is fairly easy and may already be something you have done before without realizing why you were doing it. Planks, lock-offs, and front-levers are all isometric and used regularly by climbers worldwide.
Isometric contraction exercises
Here are two simple exercises that can be performed:
- Place your palms flat against a wall
- Brace your feet firmly against the floor
- With even pressure, push continuously against the wall
- Push for 10 seconds, rest for 45 seconds, then repeat
- Press your back against the wall
- Place your feet shoulder width apart
- Lower yourself down into a seated position with you back against the wall
- Make sure your knees do not come over your toes
- Raise your arms in the air and hold the position for 15-20 seconds, rest for 45 seconds, then repeat
Moreover, the benefits of seated squats for knee rehabilitation are well documented and used by many physiotherapists. A client of mine who had surgery for a cruciate ligament injury strengthens the knee by using wall squats and holding a bridge position. If you have had any similar injuries, please check with your doctor for appropriate exercises.