Bend your knees. Use your legs. Turn your shoulders. Extend your elbow at impact. Flick your wrist. These are just some of the verbal cues that we’ve all heard countless of times. Notice any similarities? Let me give you a hint...the focus of these instructions are directed exclusively towards a body segment or part. Is this type of feedback relevant? Does it help improve technique and ultimately, performance? Let’s take one of these examples and break it down. 'Bend your knees'. How does a player interpret this cue? I mean how low should I bend my knees? Is a 90 degree bend more or less effective than a 100 degree bend? On which type of shot? Should one knee be bent more than the other? As you can see, this cue can be interpreted in a number of different ways depending on the athlete and the context.
Luckily for us, there’s a growing body of research that attempts to understand this type of verbal instruction. Researchers (in particular, Gabriele Wulf, a pioneer in the field of motor learning) have been exploring learning (and cueing) from an attentional focus perspective for years now. Attentional focus cues can be either external or internal (we'll get into the definitions below). This post will distinguish between these 2 types of foci while using research examples from tennis, along with other sports like golf and baseball. Finally, we’ll provide a few examples of internal vs external cueing as they relate to tennis - as you’ll see, a small change in wording may be all it takes to shift a cue from internal to external - but it could make a big difference in your tennis play.
Note: The examples provided at the beginning of this article are all internally focused cues.
External vs Internal Focus of Attention: What's the Difference?
Let’s first define each type of attentional focus. External focus of attention is described as “where the performer’s attention is directed to the effect of the action” while an internal focus of attention is described as “where attention is directed to the action itself” (Wulf 2007).
To clarify, external focus instructions are aimed at factors outside the body, like an implement, support surface, the trajectory of an object or a target. In tennis, for example, we could direct our focus to the racquet (it’s swing path for instance), the ball (it’s height, shape, spin, speed etc.) or hitting into a specific area of the court (target). Even from a physical training perspective, an external cue may be used. You could, for instance, direct attention to the ground. During a jump exercise for increased height/power, this type of cue could look something like this; “push the ground away from you” and/or “try to look above my hand” (or some other reference point).
An internal focus cue would direct a learner to a particular limb, or body part, in an attempt to produce the desired movement. Instructions would then be aimed at specific movements of the body. In tennis, that may mean to focus on your arm during a stroke. More specifically, you could direct your focus to specific aspects of your arm, like your wrist - “lay back your wrist” is an example of aiming your attention to internal factors. Another example may be to “turn your shoulders” when preparing to hit a groundstroke. From a physical training perspective a typical cue to increase jump height may be to “bend your knees to a 90 degree angle and extend them explosively”.
Is One Type of Focus Better than the Other?
The question is, which is more effective at enhancing learning and consequently, performance? When it comes to the scientific literature (as we’ll soon see), the effects are quite clear. In close to 100 experiments, from a variety of sports and disciplines, significant differences exist between external and internal attentional foci. More specifically, it’s external focus of attention cues that significantly and consistently outperform internal attentional focus cues. Apart from a few studies that showed slight benefits to internal cueing OR no significant difference between the 2 types of cueing, external seems to be the way to go.
But there’s a problem, according to Wulf (2013). In an interview study, more than 84% of track & field athletes reported that their coaches gave instructions that were specific to the movement of a body part or segment. Practically, we see this quite often in tennis settings - from beginners to elite performers, many students consistently receive instructions to deliberately focus and think about a particular body part when either learning a new skill or when attempting to master one.
Before we completely switch how we instruct as coaches, and what we focus on as players, let’s outline why an external focus might (key word) be more beneficial and some of the research that tells the story.
The Theory Behind Attentional Focus
In a previous post on learning in tennis, I spoke about dynamic systems and some of the work by Nicolai Bernstein. Further to that discussion, when it comes to coordination and movement control, Bernstein proposed that the processes that govern movement aspects are “delegated to subordinate levels of the nervous system, where control is less conscious” (Chow et al 2015). As outlined previously, dynamic systems theory is based on the premise that the body will self-organize itself to meet task demands. When movement occurs at a more sub-conscious level, the theory states that the goal of a particular task will be carried out more optimally. In contrast, "if the movement occurs more consciously, the upper levels of the central nervous system are more involved and this can lead to undesirable breakdown of the movement” - as Chow explains (2015).
"If the movement occurs more consciously, the upper levels of the central nervous system are more involved and this can lead to undesirable breakdown of the movement”. - Chow et al (2015) on focusing attention internally.
Interestingly, it’s internal focus of attention instructions that contribute to a conscious awareness of the desired movement, thereby inhibiting automatic processes. While the opposite is true for external focus of attention cues - they facilitate a “subconscious control of movement”. Why does focusing on internal movements function in this manner? Wulf (2013) suggests that an internal focus may act as a ‘self-invoking trigger’. In other words, when directing attention to a particular limb for example, there’s a neural representation of the self. We end up attempting to regulate our actions which does the opposite of what we’re intending to accomplish. Instead of moving with more grace, we end up increasing tension, resulting in a more ‘mechanical’ rather than an effortless movement outcome. We’ve all been there before right? You’re given feedback to keep your wrist locked at impact for example and what happens, your entire arm, shoulder, neck etc get tight - you can’t even make clean contact with the ball!
There’s another factor that contributes negatively to movement outcome when the ‘self’ gets involved (btw, if you’ve ever read The Inner Game of Tennis, by Tim Gallwey, you’ll likely have a greater appreciation for the work by Wulf and the research related to attentional focus). Because we’re more conscious about our bodily movements, we also begin to critique ourselves - with an inclination towards negative evaluations of our performance. To paraphrase Wulf, all of our thoughts, actions and behaviours influence how we perceive the movement - which ends up getting in the way of producing an effortless swing, for example. This is partly the reason Gallwey, in Inner Game, developed specific drills to get the ‘self’ out of the way. For example, he used a simple auditory drill to get his students to better focus on the ball, rather than where and how they should swing a racquet. He would get his students to say ‘bounce’ when the ball hit the court on their side and ‘hit’ at the moment of impact. What he noticed was that performance almost immediately improved. There are a number of external focus drills and cues that can help distract the ‘self’ while at the same time facilitating more automaticity in movement production. In future posts we’ll outline more of these drills but for now, let’s take a look at some research on this topic.
What Do Elite vs Non-Elite Players Focus On? A Scientific Perspective
Tennis is a precision type sport. In other words, you must be quite accurate with your shots as boundaries to where you can hit, do exist. There are a few studies that have attempted to determine whether an external or internal focus of attention in tennis would be better at improving accuracy in a variety of shots. One study by Hadler et al (2014), put the theory to work with 11 year old children (none of which had any prior tennis playing experience). The kids that were given external focus instructions outperformed those that were given internal focus instructions along with those kids who were given no instructions at all. Interestingly, there wasn’t much difference between the internal cues group and the control group - both performed equally poorly. Serve performance in both novice performers and advanced performers (Wulf et al 2002) also benefitted more from external attentional cues versus internal ones.
Similar findings have been seen in golf settings with both novice and expert performers. Wulf and Su (2007) found that external instructions were better in both novices and experts - in other words, when the attention of the players was directed at the swing of the club and a target versus some movement of the arms. Perkins-Ceccato et al (2003), however, found that internal focus instructions helped less skilled golfers while external cues helped more skilled golfers. Perhaps the skill level could be a deciding factor in what kind of instructions should be given. Let’s take a closer look.
In baseball batting (Castaneda and Gray 2007), when attentional cues were put to the test with both highly skilled and less-skilled batters, the results varied. Out of 4 different attentional conditions, highly skilled batters performed best when attention was focused on “the flight of the ball leaving the bat” - this attentional cue is considered both environmental and external. These same batters performed worse when attending to “the movement of their hands” where the focus is internal and on the skill itself. Interestingly, however, the less-skilled batters performed worse when attending to environmental cues, even when those cues were external. These batters fared best when the attention was aimed toward the execution of the skill - and there was no significant difference between external and internal instructions (although external cues were slightly better). So in less skilled performers, both internal AND external cues benefitted performance.
In less skilled performers, both internal AND external cues benefitted performance. - Based on research comparing highly skilled vs less skilled, baseball batters.
Given these findings, along with the beliefs of dynamic systems proponents (Chow et al 2015), it would appear that, although attending to external cues seem to be more impactful when it comes to learning and mastering complex motor skills, there may still be a place for internal cueing with novice athletes. In other words, it’s likely that complete beginners may benefit from some internal cueing.
Cueing Comparisons: Internal vs External
Future Research & Final Thoughts
Coaches should work together with researchers to conduct further studies with highly specific instructions, in a variety of environments (from beginning children to elite performers). This would further help to clarify the debate as at times, researchers don’t possess the know how to provide accurate and meaningful instructions. For example, simply focusing on your arm during a tennis forehand can differ greatly from focusing on a specific position of your elbow during the take-back phase of a forehand. The former cue being quite broad while the latter possessing specific characteristics that may be relevant to an elite player. Also, although similarities may exist between a variety of sport skills, differences cannot be overlooked. Analyzing specific skills within each sport may provide further insight into this topic - for example, a 1st serve return on the forehand side differs considerably compared to a cross-court neutral rally forehand.
Furthermore, the type of focus and even the intricate details of each cue are highly relevant. Elite players will likely benefit more from be external cues, compared to novices. They’ve hit enough tennis shots to know how it’s done. But even within external cueing, there exists skill specific cueing along with environmental specific cueing. For instance, if I tell a player to focus on some feature of the racquet, this would be classified as a skill based external cue. On the other hand, if I ask a player to focus on the flight of the ball or some area of the court to hit into, these would be examples of environmental based external cues. Some studies in elite performers actually point towards distal cueing as being more effective - i.e. the further the external cue from the body, the better the performance - like a target vs a racquet.
Knowing this may help direct our cueing depending on the time of year. During a competitive phase, it may be counterproductive to tell a player to focus on racquet preparation or the path etc. (even if you’re externally cueing). In this phase of a season, it may be more appropriate to bring focus to the ball, a target or even certain features of your opponent (the way they move, where they’re standing, how they prepare for different types of shots etc).
Lastly, when using internal cues, coaches are rarely interested in the outcome of the shot. In my opinion, this is a good thing - the aim is to alter some biomechanical feature. When there's a target in place, that's usually the focus. So it makes sense that the research on internal and external cueing is biased towards external - all of the measures are related to outcome. But outcome is NOT always the most important factor - there are times when technical training (i.e. the position of a limb in space), is critical. Injury prevention is just one example to use internal cueing to tweak technique.
All in all, subconscious control allows attention to be directed at other important features of the environment - which is important during competition. As we saw earlier with baseball batters, elite hitters performed better when attending to the environment. The authors proposed that this “freed-up” their attention - in other words, they weren’t thinking about the specific details of swinging a bat. They’ve hit millions of balls in the past and simply allowed automatic processes to take over based on the environmental cues they were attending to. This enables the human body to organize itself most effectively in order to execute the desired task/movement. This is also why when asked, many elite athletes cannot recall exactly how they executed a certain skill, they “just did it”. But we must know the athlete and which stage they're at - there's a continuum that exists when it comes to focus & cueing; let's not forget that.