Anthropometry - Physique Assessment

[Michael Scally MD]

Surface Anthropometry

The International Society for the Advancement of Kinanthropometry (ISAK) protocols should be followed for physical assessment of body size, shape and composition. The advantages of the ISAK surface anthropometry methods are that assessments take approximately 10 min for a restricted profile and up to 30 min for a full profile, and the equipment is readily available and easily calibrated. The methods are valid and reliable if ISAK training is undertaken to ensure correct landmarking is performed. International data are available for comparison of athlete measures for many sports.

The disadvantage of the ISAK surface anthropometry technique is that skinfold callipers compress the adipose tissue resulting in variation in measurements. Therefore, a complete data set of the proforma is obtained before repeating the measurements for the second and then third time. This may help to reduce the effects of skinfold compressibility.

Hume PA, Sheerin KR, de Ridder JH. Non-imaging Method: Surface Anthropometry. In: Hume PA, Kerr DA, Ackland TR, eds. Best Practice Protocols for Physique Assessment in Sport. Singapore: Springer Singapore; 2018:61-70. Non-imaging Method: Surface Anthropometry

 

[Michael Scally MD]

Bioelectrical Impedance Analysis

Bioelectrical impedance analysis allows measurement of total body water, which is used to estimate fat-free body mass and, by difference with body mass, body fat. An athlete appointment of 15 min is needed for body mass and standing stature measurement, electrode placement, and then 1 min of data collection.

The method is popular due to the procedure being simple and non-invasive, good portability of the equipment and its relatively low cost compared to other methods of body composition analysis. However, precision and validity can be low without a standardised protocol of assessment that includes guidance for subject presentation.

Sensitivity to monitor change of physique is low given variation in athlete presentation for testing can affect the results (e.g. levels of hydration). Training is available from equipment suppliers; however, there are no accreditation systems. The techniques to collect the data are easy; however, interpretation of the data is impeded given the black box approach to the data.

Studies that compare results from bioelectrical impedance analysis to other body composition techniques are outlined, and example reports to athletes are provided.

Kerr A, Hume PA. Non-imaging Method: Bioelectrical Impedance Analysis. In: Hume PA, Kerr DA, Ackland TR, eds. Best Practice Protocols for Physique Assessment in Sport. Singapore: Springer Singapore; 2018:101-16. Non-imaging Method: Bioelectrical Impedance Analysis

 

[Michael Scally MD]

Air Displacement Plethysmography (Bod Pod)

Air displacement plethysmography is used to measure body volume. The Bod Pod (COSMED USA Inc., Concord, CA) is an easy-to-use, convenient, non-invasive device that can accommodate a large spectrum of athletic physiques, assessing fat and fat-free mass reliably and accurately.

Estimates of body density are in close agreement to those using the hydrostatic weighing technique, with Bod Pod now considered the gold standard for assessment of body density in multi-compartment models. It often underestimates fat mass compared to other physique assessment techniques; however, this may be due to poor standardisation practices.

When undertaken in a well-controlled standardised manner, Bod Pod has proven to be an accurate and reliable technique for tracking physique changes over time. It is valuable in large athletes who may be more comfortable undertaking physique assessment via Bod Pod compared to other techniques where reliability in this population might be an issue.

Shaw G, Kerr A. Non-imaging Method: Air Displacement Plethysmography (Bod Pod). In: Hume PA, Kerr DA, Ackland TR, eds. Best Practice Protocols for Physique Assessment in Sport. Singapore: Springer Singapore; 2018:87-99. Non-imaging Method: Air Displacement Plethysmography (Bod Pod)

 

[Michael Scally MD]

Athlete Considerations for Physique Measurement

Physique traits are one of an array of variables known to influence performance of athletes across a wide range of sports. The routine monitoring of physique traits has become common practice amongst athletic populations, affording an opportunity to objectively assess the impact of training and diet and subsequently adjust these variables to optimise adaptations.

An array of techniques is available to assess the physique traits of athletes. When selecting the most appropriate technique, a range of factors should be considered, including technical (safety, validity, precision and accuracy of measurement) and practical issues (availability, financial implications, portability, invasiveness, time effectiveness and technical expertise necessary), including the ability of the technique to accommodate the unique physique traits of athletes.

Guidelines to assist with facilitating standardisation of athlete presentation prior to assessments are provided, with application to the majority of physique assessment techniques commonly applied amongst athletic populations such as dual-energy X-ray absorptiometry, air displacement plethysmography (i.e. Bod Pod) and bioelectrical impedance analysis.

The exception may be surface anthropometry given results are minimally impacted by athlete presentation.

Slater G, Shaw G, Kerr A. Athlete Considerations for Physique Measurement. In: Hume PA, Kerr DA, Ackland TR, eds. Best Practice Protocols for Physique Assessment in Sport. Singapore: Springer Singapore; 2018:47-60. https://link.springer.com/chapter/10.1007/978-981-10-5418-1_5

 

[Michael Scally MD]

Dual-Energy X-Ray Absorptiometry

Dual energy X-ray absorptiometry is used for the assessment of physique traits of athletes. Given the use of X-rays and thus exposure to radiation, specific training by a suitably accredited national organisation is required before dual energy X-ray absorptiometry can be operated, and consideration of the cumulative X-ray dose for athletes needs to be considered.

Standardisation of subject presentation (euhydrated and glycogen replete, overnight fasted and in minimal clothing) and positioning on the scanning bed (centrally aligned in a standard position using custom-made positioning aids) and manipulation of the automatic segmentation of regional areas of the scan results are necessary. The International Society for Clinical Densitometry has established good clinical practice guidelines relating to the acquisition and analysis of dual energy X-ray absorptiometry data.

Slater G, Nana A, Kerr A. Imaging Method: Dual-Energy X-Ray Absorptiometry. In: Hume PA, Kerr DA, Ackland TR, eds. Best Practice Protocols for Physique Assessment in Sport. Singapore: Springer Singapore; 2018:153-67. https://link.springer.com/chapter/10.1007/978-981-10-5418-1_13

 

[Michael Scally MD]

MacKenzie-Shalders KL. Imaging Method: Computed Tomography and Magnetic Resonance Imaging. In: Hume PA, Kerr DA, Ackland TR, eds. Best Practice Protocols for Physique Assessment in Sport. Singapore: Springer Singapore; 2018:143-52. Imaging Method: Computed Tomography and Magnetic Resonance Imaging

Magnetic resonance imaging and computed tomography are imaging techniques that provide a highly accurate measure of human body composition at the tissue-organ level. Computed tomography works through measuring the attenuation of X-rays through body tissues, whereas magnetic resonance imaging uses a strong magnetic field to align positively charged protons in the body’s tissues which are digitised to provide a greyscale image. Magnetic resonance imaging is emerging as a safe method of choice over computed tomography as it does not expose participants to radiation. Due to constraints in cost and availability, the techniques are generally only used for athletes as part of a research project or for clinical purposes.

 

[Michael Scally MD]

[OA] Buckinx F, Landi F, Cesari M, et al. Pitfalls in the measurement of muscle mass: a need for a reference standard. Journal of cachexia, sarcopenia and muscle 2018;0. https://doi.org/10.1002/jcsm.12268

Background - All proposed definitions of sarcopenia include the measurement of muscle mass, but the techniques and threshold values used vary. Indeed, the literature does not establish consensus on the best technique for measuring lean body mass. Thus, the objective measurement of sarcopenia is hampered by limitations intrinsic to assessment tools. The aim of this study was to review the methods to assess muscle mass and to reach consensus on the development of a reference standard.

Methods - Literature reviews were performed by members of the European Society for Clinical and Economic Aspects of Osteoporosis and Osteoarthritis working group on frailty and sarcopenia. Face‐to‐face meetings were organized for the whole group to make amendments and discuss further recommendations.

Results - A wide range of techniques can be used to assess muscle mass. Cost, availability, and ease of use can determine whether the techniques are better suited to clinical practice or are more useful for research. No one technique subserves all requirements but dual energy X‐ray absorptiometry could be considered as a reference standard (but not a gold standard) for measuring muscle lean body mass.

Conclusions - Based on the feasibility, accuracy, safety, and low cost, dual energy X‐ray absorptiometry can be considered as the reference standard for measuring muscle mass.

 

[Michael Scally MD]

[Thread] I frequently see misconceptions about body composition, both in the peer-reviewed literature and on good ol' social media. As such, I thought it may be helpful to share some basic information about some of the major body composition principles.⁣ [1/14]