KEY POINTS

Phase angle (PhA) is a powerful marker of cellular health, hydration, and tissue quality.
Higher PhA = better muscle quality, lower inflammation, better recovery.
Segmental and multi-frequency readings help pinpoint asymmetries and changes over time.
You can improve your phase angle with training, recovery, nutrition, and inflammation control.

INTRODUCTION

Verro just got a medical-grade body composition analyzer that costs as much as a car and now lives in the corner of our gym: the InBody 970s. I wrote an article all about it, which you can check out here. The machine spits out a mind-numbing number of metrics, but one of our favorite ones is called phase angle. Naturally, this meant I had to learn everything I could about it, and put what I learned into a blog.

So what is phase angle, and why should you care? Because it’s one of the best metrics we’ve seen for monitoring how your body is adapting to training, recovering from stress, and improving tissue quality over time. In this post, I’ll walk you through what it is, how to read it, and how we help clients improve it.

WHAT IS PHASE ANGLE?

Phase angle is a number that tells us how well your cells are functioning, especially how well they retain water and conduct electricity. During an InBody scan, a safe, low-level electrical current is sent through your body via electrodes on your hands and feet. As this current passes through your tissues, it encounters both resistance (from fluids) and reactance (from cell membranes). The InBody 970s measures how the current behaves at different frequencies and in different body segments to calculate your phase angle using this formula:

Where:

Xc: Reactance — how well your cell membranes resist changes in electric current (a proxy for cell integrity)
R: Resistance — how much your body resists electric current (mainly affected by fluid content)

High phase angle = strong, hydrated, high-functioning cells.
Low phase angle = inflammation, low muscle mass, dehydration, or illness.

HOW THE INBODY 970S MEASURES PHASE ANGLE:

Unlike cheaper BIA devices, the 970s measures PhA at multiple frequencies (5, 50, 250 kHz) and body segments (each arm, leg, and trunk). This gives us:

5 kHz: Measures extracellular water (inflammation, edema)
50 kHz: The standard frequency used in most BIA devices. It penetrates both intracellular and extracellular compartments, giving a general overview of tissue health and is typically used for total-body PhA comparison.
250 kHz: Measures intracellular health (muscle quality, hydration)
Trunk vs limbs: Highlights regional changes and muscular asymmetries

WHAT IS A GOOD PHASE ANGLE?

It depends on age, sex, and training status, but here’s a general guide for healthy, active adults:

What We Look for at Verro

Baseline score: What’s your starting point?
Asymmetries: Is one leg or arm lower than the other by >10%? That’s a red flag.
Trends: Is PhA trending up or down over time?
Frequency comparison: Is your 250 kHz PhA improving (muscle quality)?

TIERED PHASE ANGLE STRATEGY LIST

Not all strategies for improving phase angle are created equal — some are foundational, while others are more nuanced and powerful but require specialized tools or programming. At Verro, we use a tiered system to help clients start with the basics and work up to advanced tactics that align with their goals and training history. Here's how we break it down:

Tier 1: Essentials (Everyone Should Do This)

Resistance training: Prioritize full-body compound lifts 2–4x/week. Building and maintaining lean muscle mass has been positively associated with higher phase angle due to increased intracellular water and improved cell membrane integrity (Barbosa-Silva et al., 2005).
Protein: Eat 1.6–2.2 g/kg daily to support lean muscle mass, promote recovery, and preserve tissue quality. Adequate protein intake contributes to a higher intracellular-to-extracellular water ratio and helps maintain the cellular integrity that underlies a high phase angle. Consuming protein evenly throughout the day, especially around workouts, may also enhance muscle protein synthesis and support cell membrane structure (Tipton et al., 2007).
Hydration: Drink water throughout the day. Consider electrolytes if you train hard or sweat a lot. Proper hydration status, especially maintaining intracellular-to-extracellular water balance, has been shown to positively influence phase angle measurements (Lukaski et al., 2017).
Sleep: Aim for 7–9 hours of quality sleep each night. Deep sleep supports cellular repair, protein synthesis, and tissue remodeling — all of which are crucial for improving phase angle. Poor sleep has been linked to increased inflammation and impaired glucose metabolism, both of which can negatively impact PhA. Recovery happens when you're not just resting, but actually entering the deep stages of sleep that trigger hormonal cascades and cellular cleanup (Van Cauter et al., 2008).

Tier 2: Optimal Strategies

Creatine: Creatine helps draw water into muscle cells, which increases intracellular hydration and improves cell volume — both linked to higher phase angle. It also supports ATP production and muscle recovery. We recommend supplementing with 3–5g/day consistently for best results (Buford et al., 2007).

Anti-inflammatory foods: A diet rich in omega-3 fatty acids, leafy greens, turmeric, and berries may help reduce chronic inflammation that otherwise increases extracellular water and lowers phase angle. Supporting anti-inflammatory pathways through nutrition helps create an internal environment more favorable to cellular recovery and function.
Unilateral training: Training one side at a time allows you to identify and correct asymmetries in strength, mobility, and muscle quality. Since we track PhA by limb, even small imbalances can show up. Addressing them helps bring lagging limbs up to par and improves total-body symmetry.
Monitor trends: Tracking your segmental and frequency-specific PhA over time allows us to see how your body responds to training, deloads, and recovery. Instead of guessing whether you're overreaching or adapting, we use this data to make better-informed decisions in your program.

Tier 3: Advanced Optimization

Eccentric overload: This approach emphasizes the lowering phase of a lift, where you’re strongest and can tolerate more load. It leads to denser muscle tissue and greater mitochondrial adaptations. Research has shown that eccentric training can enhance muscle fiber recruitment, increase intracellular water retention, and improve overall cellular function — all of which are factors that positively influence phase angle (Douglas et al., 2017). At Verro, we use the Voltra 1 to make eccentric overload safe and accessible, helping clients increase phase angle through high-quality muscle growth.
Red light therapy: Emerging research suggests red and near-infrared light may improve mitochondrial function, enhance cellular energy production, and reduce inflammation — all of which support better phase angle scores (Zhang et al., 2014).
Cold exposure: When done strategically, cold exposure (like cold plunges) may reduce inflammation, improve circulation, and help regulate fluid shifts that affect extracellular water levels. Studies suggest that regular cold exposure may reduce systemic inflammation markers like CRP and IL-6 and positively influence vascular tone and lymphatic drainage (Machado et al., 2016; Bleakley & Davison, 2010).
Phase-based programming: At Verro, we adjust your training plan based on trends in your phase angle. If we see drops, we may incorporate deloads, emphasize recovery, or tweak intensity. If it’s climbing, we know adaptation is happening, and we should keep pushing. Individualized autoregulation based on physiological feedback like PhA has been proposed as a way to optimize recovery cycles and prevent overtraining (Halson, 2014; Saw et al., 2016).

CONCLUSION

At Verro, we believe every workout should deliver the best possible return on investment — and phase angle is one of the best tools we’ve found for measuring that return. It’s non-invasive, repeatable, and sensitive to changes that matter: muscle quality, inflammation, recovery, and cellular health.

Whether we’re adjusting your program, assessing a rehab client, or testing a new supplement, PhA gives us real-time feedback on how your body is responding.

If you’d like to check your phase angel, feel free to book a free consultation with a team member.

REFERENCES

Barbosa-Silva, M. C., Barros, A. J., Wang, J., Heymsfield, S. B., & Pierson Jr, R. N. (2005). Bioelectrical impedance analysis: population reference values for phase angle by age and sex. The American Journal of Clinical Nutrition, 82(1), 49–52. https://pubmed.ncbi.nlm.nih.gov/16002801/
Bleakley, C. M., & Davison, G. W. (2010). What is the biochemical and physiological rationale for using cold-water immersion in sports recovery? A systematic review. British Journal of Sports Medicine, 44(3), 179–187. https://pubmed.ncbi.nlm.nih.gov/19505961/
Buford, T. W., Kreider, R. B., Stout, J. R., Greenwood, M., Campbell, B., Spano, M., ... & Antonio, J. (2007). International Society of Sports Nutrition position stand: creatine supplementation and exercise. Journal of the International Society of Sports Nutrition, 4(1), 6. https://pubmed.ncbi.nlm.nih.gov/17908288/
Douglas, J., Pearson, S., Ross, A., & McGuigan, M. (2017). Chronic adaptations to eccentric training: a systematic review. Sports Medicine, 47(5), 917–941. https://pubmed.ncbi.nlm.nih.gov/27699674/
Halson, S. L. (2014). Monitoring training load to understand fatigue in athletes. Sports Medicine, 44(2), 139–147. https://pubmed.ncbi.nlm.nih.gov/24791915/
Lukaski, H. C., & Raymond-Pope, C. J. (2017). Bioelectrical impedance analysis: theory, practice, and future. Journal of Electrical Bioimpedance, 8(1), 97–107. https://pubmed.ncbi.nlm.nih.gov/28936424/
Machado, A. F., Ferreira, P. H., Micheletti, J. K., de Almeida, A. C., Lemes, Í. R., Vanderlei, F. M., ... & Pastre, C. M. (2016). Can water temperature and immersion time influence the effect of cold water immersion on muscle soreness? A systematic review and meta-analysis. Sports Medicine, 46(4), 503–514. https://pubmed.ncbi.nlm.nih.gov/26714810/
Saw, A. E., Main, L. C., & Gastin, P. B. (2016). Monitoring the athlete training response: subjective self-reported measures trump commonly used objective measures: a systematic review. British Journal of Sports Medicine, 50(5), 281–291. https://pubmed.ncbi.nlm.nih.gov/26560408/
Tipton, K. D., & Wolfe, R. R. (2007). Protein and amino acids for athletes. Journal of Sports Sciences, 22(1), 65–79. https://pubmed.ncbi.nlm.nih.gov/14971434/
Van Cauter, E., Spiegel, K., Tasali, E., & Leproult, R. (2008). Metabolic consequences of sleep and sleep loss. Sleep Medicine, 9, S23–S28. https://pubmed.ncbi.nlm.nih.gov/18929315/
Zhang, Y., Song, S., Fong, C. C., Tsang, C. H., Yang, Z., & Yang, M. (2014). cDNA microarray analysis of gene expression profiles in human fibroblast cells irradiated with red light. Journal of Investigative Dermatology, 124(3), 514–521. https://pubmed.ncbi.nlm.nih.gov/15086552/
Disclaimer
The information provided in this article is for educational and informational purposes only and is not intended as medical advice, diagnosis, or treatment. Phase angle measurements, like all bioelectrical impedance analysis outputs, should be interpreted in the context of a comprehensive health and performance assessment. Always consult with your physician or a qualified healthcare provider before making any changes to your diet, exercise, or wellness routines. At Verro, we use phase angle data as part of an evidence-informed strategy to support performance, recovery, and long-term health — not to diagnose or treat medical conditions.

DISCLAIMER

This article is for informational and educational purposes only and is not a substitute for medical advice, diagnosis, or treatment. Always consult with a qualified healthcare provider or certified fitness professional before starting any new training program, especially if you have any pre-existing health conditions or injuries. Individual results may vary, and adjustments to training volume, exercise selection, and intensity should be made based on your personal recovery capacity, experience level, and goals.

Phase Angles: The Unknown Metric That Tracks Cell Health