Y Balance Test™
The Y Balance Test™ (YBT) is a simple, yet reliable, test used to measure dynamic balance.
Learn how to effectively carry out tests on your athletes without spending a penny. You’ll master performance testing, field tests, gym tests and more for free.
By Owen Walker
18 Sep 2016 | 5 min read
Contents of Article
The Y Balance Test™ was developed to refine the lengthy process of conducting the Star Excursion Balance Test. As such, most of the supportive research for the Y Balance Test™ is based on the investigations conducted on the Star Excursion Balance Test. Nevertheless, the Y Balance Test™ has not only proven itself to have a high-level of test–retest reliability, but also to be a sensitive indicator of injury risk amongst athletes.
Keywords: Y Balance Test, dynamic balance, injury risk, composite score.
The Y Balance Test™ (YBT) is a simple, yet reliable, test used to measure dynamic balance (1). It was developed to standardise the modified Star Excursion Balance Test (mSEBT), improve its practicality, and make it commercially available (1). Since then, the YBT has gone on to become an extremely popular test due to its simplicity and reliability.
The YBT requires the athlete to balance on one leg whilst simultaneously reaching as far as possible with the other leg in three separate directions: anterior, posterolateral, and posteromedial. Therefore, this test measures the athlete’s strength, stability and balance in various directions. The YBT composite score is calculated by summing the 3 reach directions and normalizing the results to the lower limb length, whereas asymmetry is the difference between right and left limb reach (1) – this is explained in greater detail in the scoring system section.
Whilst previous injury or surgery appears to have no impact on test performance in collegiate athletes (1), the test has been shown to have strong relationships with knee flexor and hip abductor strength (2). Though little research has been conducted on the YBT and athletic injury risk, most of the assumptions regarding injury risk are extracted from research on the Star Excursion Balance Test (SEBT) due to its large similarity to the YBT. For example, an anterior reach asymmetry of greater than 4cm during the SEBT has been suggested to predict which individuals are at risk of lower limb injury (3).
However, other researchers have found that only female athletes with a composite score of less than 94% of limb length were at greater risk of injury (3). More recent research in collegiate American football players has shown that athletes with a composite score of less 90% are 3.5 times more likely to sustain an injury (4). Additional research has also highlighted that poor performance on the SEBT is related to chronic ankle instability (5). All of this information suggests that each sport and population (e.g. gender) appear to have their own injury risk cut-off point (3, 4).
Credit to TSRHChildren for this great video
Balance, otherwise known as ‘postural control’, can be defined statically as the ability to maintain a base of support with minimal movement, and dynamically as the ability to perform a task while maintaining a stable position (6, 7). In a chaotic sporting environment, the ability to maintain a stable position is vital not only for successful application of the skill, but to also reduce the likelihood of injury (8, 3, 4). As a result, it may be of great interest to test and monitor an athlete’s dynamic stability.
It is important to understand that whenever fitness testing is performed, it must be done so in a consistent environment (e.g. facility), so that it is protected from varying weather types, and with a dependable surface that is not effected by wet or slippery conditions. If the environment is not consistent, the reliability of repeated tests at later dates can be substantially hindered and result in worthless data.
Required Equipment
Before the start of the test, it is important to ensure you have the following items:
Test Configuration
Video 1 displays the test configuration and procedure for the YBT. This setup and protocol must be adhered to if accurate and reliable data is desired.
To plan an effective warm-up, the strength and conditioning coach must first understand the mental, physiological, and biomechanical demands of the training session or sport before they attempt to prepare the athlete for these precise demands. In most circumstances, these demands are identified during the need analysis.
For example, if a strength and conditioning coach is planning a warm-up for some 1-repetition maximum (1RM) testing, then they might want to consider what the mental, physiological, and biomechanical demands of that session are. For mental preparation, the coach may encourage the athletes to arrive well-rested and to bring personal self-motivating music to listen to whilst testing – as this has been repeatedly shown to improve performance (24). To prepare them physiologically, the coach may adopt a warm-up routine with mimics’ similar physiological demands to 1RM testing, such as high-force/strength, long-rest exercises. In terms of biomechanical preparation, stretches, dynamic movements and exercises similar to those being performed during testing would be appropriate (e.g. back squatting).
Alternatively, if a strength and conditioning coach is designing a pitch-based warm-up for a ‘short and sharp’ technical session for football (soccer), then the warm-up should be designed specifically for that session and therefore may look very different to the previous 1RM testing example. The mental preparation may likely be very different, as the players’ mental readiness may be stimulated by competing against other players – as an example. Physiologically, if the technical session demands high-work volumes with short recovery periods, and thus a high cardiovascular demand, then the warm-up should aim to produce similar or even replicate the intensities the athletes will be exposed too. From a biomechanical standpoint, the adopted movements should have biomechanical similarities to the movements which will be prevalent during the technical session. This may include things such as lunges, directional changes, jumping, and twisting movements.
Remember that the warm-up can be structured effectively and strategically using the RAMP protocol and that the content/ exercises should replicate those of the session the athletes are preparing for.
Test Procedure
Warm-up
Conducting the test
IMPORTANT: This testing procedure is explained when using the YBT kit.
NOTE: Failed attempts include the following:
With the test complete and all performances recorded, the test administrator can then calculate the athletes YBT performance scores using any of, or all of, the following three equations (9):
The YBT has proven to have very good levels of interrater test–retest reliability (ICC = 0.80 – 0.85) when measured by entry-level doctorate physical therapy students (9). In support of this, another study found that ICC (Intraclass Correlation Coefficient) for intrarater reliability ranged from 0.85 to 0.91 and for interrater reliability ranged from 0.99 to 1.00. Composite reach score reliability was 0.91 for intrarater and 0.99 for interrater reliability (10).
Some coaches believe that reading one article will make them an expert on Performance Testing. Here’s why they’re wrong…
Performance Testing entails many, many topics. By choosing to simply read up on The Y Balance Test and ignore the sea of other crucial Performance Testing topics, you run the risk of being detrimental to your athlete’s success and not realising your full potential.
To make you an expert coach and make your life as easy as possible, we highly suggest you now check out this article on The Modified BASS Balance Test.
Reference List (click here to open)
Owen Walker MSc CSCS
Founder and Director of Science for Sport
Owen is the founder and director of Science for Sport. He was formerly the Head of Academy Sports Science and Strength & Conditioning at Cardiff City Football Club, and an interim Sports Scientist for the Welsh FA. He also has a master’s degree in strength and conditioning and is a NSCA certified strength and conditioning coach.
Learn how to effectively carry out tests on your athletes without spending a penny. You’ll master performance testing, field tests, gym tests and more for free.