Phase Angle

As chiropractor and former division I strength and conditioning coach I strongly believe that goal setting is something that should be quantifiable.  While there is a place for qualitative data, nothing speaks to outcome-based results like the presentation of numerical figures.  While this can be a fantastic way to evaluate the progress of individuals in a personal training, group, or team scenario to monitor performance and recovery, there are many parallels that should be acknowledged from a health perspective. 

For example, in a scenario in which optimal performance is looking to be achieved, the vertical jump serves as a tremendous indicator of power output and central nervous system recovery.  In order to identify a lack of recovery, coaches look to identify outliers in vertical jump trends over the course of an extended time period.  In the event that vertical jump height falls off significantly on any given day- behavior modification, adjustment in training volume, or an adjustment in load accumulation during a sport practice may be warranted.

In comparison, health data is rarely tracked and compared in detail over the course of time. When blood labs are taken at an annual physical the information provided back to the patient is often minimal.  Trends are rarely viewed as important as long as the patient falls within a very wide standard reference range during current testing.  Upon closer examination however, trends in health data can tell an important story.  In my opinion, identifying the root cause of a symptom provides substantially more value than providing a named diagnosis.  Consequently, in order to help anyone, referencing the levels of organization of the human body should always be viewed as a foundational necessity as any dysfunction of the human body can be traced to the cellular level.  Getting even more specific, the cell membrane could arguably be viewed as the most critical component of any individual cell.  So, if there was a metric to test cellular health, I felt that it could certainly bring value to the patients who I serve.

Bioelectrical impedance analysis (BIA) is commonly recognized for the measurement of body composition.  It works by sending an alternating electrical current throughout the body and is measured based off resistance and reactance of the body to these currents.  While resistance can identify tissue hydration status due to water conductivity, reactance is used to determine the amount of energy that can be accumulated in tissues and reflects the capacitance of the cell membrane.  Utilizing this information, BIA data can formulate a variable called phase angle. 

While phase angle is continually gaining more popularity amongst progressive clinicians, it is relatively unknown for most.  Research indicates that measurement of phase angle is a strong reflection of functionality, nutrition status, and integrity of the cell membrane.  When phase angle was studied in terminally ill patients, researchers found that a 1 degree decrease in phase angle was associated with greater risk of mortality.  Additional studies have found relationships between interleukin-6 levels (an inflammatory marker) and phase angle as well.  These studies indicate that a decrease in phase angle could very well be the result of chronic inflammation.  In addition, we do know that phase angle will generally be higher in males then females due to differences in muscle mass and that that as aging occurs there will be a downward trend in this metric.  In the healthy adult, phase angle ranges between five and seven.  However, maintaining a phase angle at or above seven would be in the best interest of all adults if their intention is to thrive as they progress throughout life. 

In order to improve phase angle proper nutrition and supplementation combined with resistance training protocols focusing on large compound movements have been shown to be effective.  For example, a study published in 2016 found that a 12-week progressive resistance training program performed by women 60 years of age and older resulted in an improvement in phase angle and intracellular water levels.  This suggests that a properly conducted resistance training program can influence cellular health and fat-free mass in specific populations.  More importantly, we must consider that the loss of muscle mass at a rate of 1-2% per year is defined as sarcopenia and can lead to a variety of consequences such as disability, mortality, and elevated healthcare costs.  Proactively combatting this simply by acknowledging trends in phase angle can serve as motivation for both improved nutrition and  participation in a progressive resistance training program.  This can provide constructive feedback as to whether the chosen roadmap is in fact effecting the body in a positive manner.

The value of phase angle lies in the context of its application.  If used properly this measurement will be able to detect disease when a patient is asymptomatic and also provide unbiased insight as to the efficacy of any resistance training program or nutrition protocol.  I believe our standards should never fall short of giving each person we work with the opportunity to thrive throughout their entire life.  Phase angle provides us the opportunity to take one step closer to achieving this standard.

References

Basile, C., Della-Morte, D., Cacciatore, F., Gargiulo, G., Galizia, G., Roselli, M., … Abete, P. (2014). Phase angle as bioelectrical marker to identify elderly patients at risk of sarcopenia. Experimental Gerontology, 58, 43–46. https://doi.org/10.1016/j.exger.2014.07.009

Di Vincenzo, O., Marra, M., & Scalfi, L. (n.d.). Bioelectrical impedance phase angle in sport: a systematic review. https://doi.org/10.1186/s12970-019-0319-2

Garlini, L. M., Alves, F. D., Ceretta, L. B., Perry, I. S., Souza, G. C., & Clausell, N. O. (2019). Phase angle and mortality: a systematic review. European Journal of Clinical Nutrition, 73(4), 495–508. https://doi.org/10.1038/s41430-018-0159-1

Halson, S. L. (2014, November 1). Monitoring Training Load to Understand Fatigue in Athletes. Sports Medicine, Vol. 44, pp. 139–147. https://doi.org/10.1007/s40279-014-0253-z

Luebbers, P. E., Potteiger, J. A., Hulver, M. W., Thyfault, J. P., Carper, M. J., & Lockwood, R. H. (2003). Effects of Plyometric Training and Recovery on Vertical Jump Performance and Anaerobic Power. Journal of Strength and Conditioning Research, 17(4), 704–709. https://doi.org/10.1519/1533-4287(2003)017<0704:EOPTAR>2.0.CO;2

Peacock, C., Mena, M., Sanders, G., Silver, T., Kalman, D., & Antonio, J. (2018). Sleep Data, Physical Performance, and Injuries in Preparation for Professional Mixed Martial Arts. Sports, 7(1), 1. https://doi.org/10.3390/sports7010001

Souza, M. F., Tomeleri, C. M., Ribeiro, A. S., Schoenfeld, B. J., Silva, A. M., Sardinha, L. B., & Cyrino, E. S. (2017). Effect of resistance training on phase angle in older women: A randomized controlled trial. Scandinavian Journal of Medicine and Science in Sports, 27(11), 1308–1316. https://doi.org/10.1111/sms.12745