Monday, May 30, 2011

Difficulty Analysis: The Ingredients of Movement

"That hold is tweaky."
"That foot is too high."
"That move is huge."

Is it so simple? What makes movement hard? It's easy to try a move, "feel" how hard it is, and simply end your analysis there. However, climbing is a technical activity, and the levels of complexity are almost endless. Many of the best routesetters simply intuitively know what's hard about a move, and over time that skill can be developed. But it will help to have some of the basics down to make off-the-cuff setting, tweaking and offering forerunning advice easier. Here's a few of the basics of understanding what makes a move feel hard.

Mechanical Advantage

Mechanical advantage is the term used to describe a move that can be altered in difficulty, significantly or subtly, by a subtle tweak in body position. Here are the major points of mechanical advantage, and the type of moves for which they might apply.

Straight arms - The quintessential example can be found in every coaches' rallying cry to "straighten your arms!" Straight arms use the musculoskeletal structure as a support system, rather relying on the inferior lactic-acid-vulnerable forearm muscles. Any method that allows the climber to achieve straight arms can provide considerable rest opportunities. Three of the easiest contributors to a rest position are: Holds facing straight up and down with feet directly below them; holds facing inward in a dihedral; and holds facing outward on an arete. These rest spots can be quickly tweaked or eliminated by changing the directionality of the restable hold to something less mechanically preferable.

Hold factors - the "incutness" or depth of a hold can allow for significant mechanical advantage, by giving the climber more breathing room in their body position. Larger holds, even slopier ones, provide some mechanical advantage by letting the climber's larger hand and arm muscles do the work without having to redirect their energy and tension through the smaller muscles of the fingers.

Plumb line potential via body position - a mouthful, but the best way of describing what is essentially "ideal body positioning." The best way to understand is simply to look at two angles when considering a move. Angle 1 is the angle of the climber's arm when holding the hold, or more accurately, the angle of a line drawn from the climber's center of gravity to the center of the hold. Angle 2 is the plumb line of the hold. The smaller the difference between these two angles, the more mechanical advantage exists in the route. Often moves with massive discrepancies between these two angles end up feeling "tweaky" or just plain difficult. Plumb line is without question the fastest way to make a route more difficult. A tiny twist in the directionality of a hold takes only a few seconds (compared to at least a minute to change out a hold or foothold) and can change a move from comfortable to desperate instantly.

Ankles - One sometimes overlooked mechanical advantage is the ankle. The larger the foothold, the easier it is for a climber to use the big muscles of their leg, rather than redirect tension through the complicated and smaller muscles of the foot. Huge feet with bad handholds is a great way to test or train finger strength, but simply won't force the climber to engage their core as much as vice versa. In dihedrals, this mechanical advantage can be a nightmare, as feet usually considered completely awful can be enough for the climber to relax their ankle.


Travel is my catchall word for the physical movement factors of a move. A frequent complaint among shorter climbers is that moves are too big. Being able to watch a climber try a move and understand specifically which part of the move is giving them difficulty can be a powerful asset for a routesetter. Working efficiently with forerunners for competitions and being able to communicate with and appease a gym community will both require cultivating the ability to understand why a move is "big."

Travel time - the duration of time that the climber must maintain or create body tension or momentum to execute a move. Some moves are better done quickly, and some slowly. Generally speaking, more vertical or slabby routes will be forgiving and allow longer duration movement; simply because of the imposed demand on the body to maintain tension, steeper walls require more alacrity. In some cases, such as unwinding from a deep cross through on a steep wall, the movement must be executed in a manner many climbers refer to as being simultaneously slow and fast. In many cases, a move will have a tipping point, where the move can be executed in a static manner up to that point, and the climber must alter their position to create momentum and complete the move.

Travel distance - simply the physical size of the move - but notably, not as it appears to many climbers. For instance, if the left hand is low on an undercling at waist height, and the right hand on a crimp above head height, moving to the next hold a few feet above the climber can be a body-height-sized move. However, if the crimp allows for a match, the size of the move is cut in half. This principle is why matchable holds are a huge no-no for forcing sequences (unless the match is the intended sequence) - and, due to the size of kid-fingers, why it is more difficult to set problems that are equitable for children and adults.

Body Position - the effects of body position on travel can't be easily summarized, but the most prominent effects are:
  • Twisting during travel - some moves will require the climber to twist in or out while making momentum in another direction. This allows the climber to maintain hip-wall proximity, maximize reach, and prepare to create tension in the body position that the next hold necessitates.
  • Traveling with the lower body - ankle, knee, and hip extension are all different factors in creating more distance in a reach during travel. Some moves will necessitate or favor different methods of reach - for instance, with big footholds, many climbers neglect to fully extend their ankle, because it is comfortable in the relaxed position. Climbers who are unused to slab climbing often don't have the trust and tension necessary to extend their ankles all the way. And, contrarily, many climbers on a steep wall will lack the body tension to extend through the knees and hips fully while moving upward.
  • Traveling with the upper body - reaching by extending the shoulders and elbows is a given, but for some moves, proper posture can affect a climbers reach. Often the trunk can be rotated one way at the hips, and another at the shoulders, to provide a bit more reach. This occurs frequently during heel hook moves on aretes and during the opening movement of a big barn door move. Other times, the two work in tandem.


Momentum is a crucial part of any move, no matter how static. Even an extremely secure, slow move requires generating force on a vector. Being a successful climber requires having a robust knowledge of generating, controlling and canceling momentum. Being a good routesetter depends upon being able to force the climber to call on that knowledge.

Generation through the elbows - necessary for some moves, but far fewer than the average climber thinks. There's a good chance if a climber thinks a move feels hard, they're starting with their elbows and following with their legs. Getting climbers out of this habit is an age-old problem for routesetters. For hard undercling moves, elbow generation becomes a necessity, as the legs will often be fully extended just to be in position.

Generation through the shoulders and back - for gym rats with chronic burl-itis, #2 after elbows. On the steepest walls, creating swing before a move, performing come-in moves and many forms of foot cutting movement necessitate shoulder momentum. Often flexing at the elbows first is not possible, as the holds are poor and it will result in a loss of body tension.

Generation through the hips - hip extension is a popular way to start moves, especially moves that trend sideways. Pulling in with the hips to rock over a foot before pushing off of it is also a common use of hip momentum.

Generation through the knees - generally speaking the most powerful momentum generation tool in a climber's toolbox. Many moves start at the knees. Placing feet to the side, angling them obtusely, or otherwise hindering vertical footwork can help to cancel out knee momentum.

Other methods - the "nod" move, notably, is used by some strong climbers with great success. The pogo or "moon kick" would also be a great example of an unorthodox method of momentum generation.

Setting a problem that requires multiple types of momentum is a good challenge for a setter, and can provide a well-rounded power testpiece for climbers.

Accuracy and Precision

How "accurate" a move must be can be a huge factor in discerning why the move is difficult. Major players in the precision requirements of a move can be:

  • Speed and momentum - the more momentum a climber has during a move, the harder it is to hit a hold perfectly, without over- or undershooting.
  • Body positioning - coming out of or in to very specific body positions can be stressful on the accuracy of a move. Hitting gastons can be notoriously picky on body position, and getting the shoulder and hip positioning right can be mentally complex enough that hitting the fingers right on the hold becomes difficult.
  • Hold size, obviously, is a factor in precision. Slapping enormous feature-slopers doesn't usually require a ton of precision, except in cases where overshooting will bring the climber off of their launch hold. Outdoors, slopers can require precision down to the individual grains in the rock. Indoors, requiring that level of precision on slopers is difficult (but possible.) When setting for precision, many setters will automatically retreat to pockets, and the benefits for that tactic speak for themselves.
Other factors

Obviously there are myriad other elements that come into play for movement difficulty - to name a few, I've ignored balance, breath control, endurance factors, and only glossed over the basics like hold size and distribution, countless aspects of foothold placement, etc. But this should be a good start to being able to analyze what makes a move 'hard.'

Morphology in combination with the factors in this article makes the entire topic exponentially more complicated than can be covered in a blog post. Climb with a morphologically diverse group of climbers and you will quickly recognize patterns to which moves each body type struggles on. Developing that intuition is the only way to learn how to do some of the most basic tasks required of a routesetter:
  1. To set movement that is equitable for different body types, and still performed the same (or similarly)
  2. To understand, without having to ask or watch someone try it, what makes a move feel difficult
  3. To be able to accurately and quickly look at, analyze and constructively criticize a boulder problem (an extension to #2 in that it requires actual communication)
  4. To be able to change a move to add or remove difficulty in the most efficient possible manner.
I will probably return to this overwhelmingly complex topic some time in the future. For now, happy setting!


  1. Excellent post, lots of thought when into this. Keep it up!

  2. Nice article - once again :)

  3. Great article. One thing though... I'm not farmiliar with the "nod" move. Could you please elaborate on this a bit.
    Also, what is "burl-itis"?

  4. Likewise, but also wondering what the "nod" move is.

  5. Hi guys,

    Sorry it took me so long to get to this. I looked for a while for a good example of the nod move. It's hard to find a good specific shot of it, but if you watch certain climbers, you'll pick up on it. Dai Koyamada does it quite a bit - in fact, I think shorter climbers tend to do it more often.

    People often forget that the head weighs quite a bit! Throwing that weight forward as you begin upward motion can be a good way to keep your hips against the wall as you move.

    Similarly, you often see climbers straining as they hit a move, with their head snapping backwards to full extension. That weight swinging backwards is a lot of extra stress and tension to generate through your shoulders. Nodding before some moves can serve to prevent that extra swing from being necessary.

    I hope that clears it up - sorry I don't have a good video of this. I'm catching up on posts as it is ;)

  6. Great post!
    Do you give tips on setting moves that are equally difficult for climbers of different heights and with different reaches? I'm quite short and in order to "Kim-proof" problems, (because I have really good technique) one of the setters I work with just puts in big reaches justifying them by saying it'll make me need to get stronger... the only problem is that the route's grade is then dependent on your height. I try to make moves more difficult not by putting the holds further apart, but by making them more difficult to hold (size and directionality). Is there anything else you could suggest?

  7. Kim,

    You're already on the right track. Directionality is the key to forcing good movement, much more so than drive distance. In no particular order, here's a brain dump to try to answer your question:

    Feet directly under the climber and downward pulling holds creates a scenario where the climber can move vertical a great distance. Try to couple downward pulling holds with more complex foot options; in scenarios where the climber has great foot options, try to offer more complex hand movements. There's not a lot of breathing room between moves being forced and not reachy, and having taller climbers be able to skip sequences. The key is in the body position.

    Lock the climber in - this doesn't mean be scrunchy, it just means positions should require a bit of core power to maintain.

    Stronger climbers (not just taller climbers) are always going to be able to skip sequences by properly turning in their hip, having good use of momentum, etc. Focus on your target audience.

    I often find that really poor directional slopers are great for forcing tiny moves, as they keep the climber within a very small margin of body positions. Incut holds allow the climber to move their hips further away form the wall.

    That all being said, definitely keep working on your power - especially if it frustrates you. Part of being a good setter is being a well-rounded climber.