Preparing for Your ECAL Metabolic Test
Accurate metabolic data starts with the right preparation.
The ECAL indirect calorimeter measures your resting metabolic rate with clinical precision. It analyses every breath you take during the test, comparing inspired against exhaled gasses like oxygen and carbon dioxide to build a complete picture of how your body produces energy at rest. That level of sensitivity means that preparing for ECAL properly matters. What you eat, drink, and do in the hours before your test directly affects the accuracy of your results. This guide covers everything you need to know before your appointment.
BEFORE Your Test
Your resting metabolic rate is exactly that: the energy your body burns at complete rest. The ECAL indirect calorimeter is sensitive enough to detect small shifts in your metabolism caused by food digestion, caffeine stimulation, or residual exertion from a recent workout. If any of these are active in your system during the test, your results will reflect a temporarily elevated metabolic state rather than your true baseline.
Following the pre-test protocol below ensures the ECAL captures your genuine resting metabolism. This gives you an accurate foundation for nutrition planning, caloric targets, and understanding how efficiently your body uses fat and carbohydrates for fuel.
If you are booking an ECAL test alongside an InBody 970 body composition scan, review the Preparing for InBody guide as well. Both tests have overlapping preparation requirements, but ECAL’s fasting window is stricter.
The Pre-Test Protocol
No alcohol or caffeine for 12 Hours Before Your Test
Both are metabolic stimulants. Alcohol disrupts fat oxidation pathways and can elevate your metabolic rate for hours after consumption. Caffeine directly stimulates your central nervous system and increases energy expenditure. Even a single coffee the morning before an afternoon test can skew your results.
No strenuous exercise for 12 Hours Before Your Test
Intense physical activity elevates your metabolism well beyond the session itself. Your body continues burning energy at an elevated rate during recovery, tissue repair, and glycogen replenishment. Training within 12 hours of your test means the ECAL will measure recovery metabolism, not resting metabolism.
No food or drink except water from 4 to 12 Hours Before Your Test
Digestion is a metabolically active process. Your body expends energy breaking down, absorbing, and processing nutrients for hours after a meal. This thermic effect of food elevates your metabolic rate above its true resting baseline. A fasting window of 4 hours (minimum) to 12 hours (maximum) ensures digestion is complete before testing begins. If you use insulin, adjust your dosing and fasting window accordingly and let Steve know at check-in.
No hot or cold therapies for 4 Hours Before Your Test
Saunas, ice baths, hot showers, and cold plunges all force your body to regulate its core temperature. This thermoregulatory response significantly increases energy expenditure and can persist for hours. Avoid any extreme temperature exposure in the 4 hours before your test.
Continue Prescription Medications
Take all prescribed medications on your usual schedule. Do not skip or adjust doses for the purpose of testing. If you have questions about specific medications, let Steve know when you book.
Continue Drinking Water
Continue drinking water as normal right up to your appointment. Hydration does not affect metabolic readings. However, if you are also booking an InBody 970 scan at the same appointment, minimise water intake for the final 2 to 3 hours before your session, as fluid levels affect body composition measurements.
What CLOTHING to wear
There is no specific dress code for an ECAL metabolic test. Wear whatever is comfortable. The test is performed while you sit or recline in a relaxed position, so restrictive clothing is the only thing to avoid.
If you are completing both an ECAL test and an InBody 970 scan at the same appointment, refer to the Preparing for InBody clothing guidelines as well, since the InBody scan requires light clothing, bare feet and contact with hand and foot electrodes.
What happens AT YOUR APPOINTMENT?
Here is exactly what to expect from the moment you arrive. No surprises.
Getting Comfortable
Steve will guide you into a seated or reclined position. The goal is complete physical relaxation. Your body needs to be at rest for the ECAL to measure your true baseline metabolism. There will be enough time to adequately relax before your test actually starts.
Nose Clip and Mouthpiece
A soft nose clip is placed over your nose to ensure all breathing passes through the mouthpiece. The mouthpiece connects to the ECAL unit and captures every breath for analysis. It may feel unusual for the first few seconds, but most people adjust quickly.
The Breathing Test
Once the mouthpiece is in place, all you need to do is breathe normally. The ECAL analyses the ratio of inspired oxygen to exhaled carbon dioxide (as well as several other factors associated with your gas exchange) in real time. The test takes approximately 5 to 8 minutes. Stay relaxed, breathe at your natural pace, and avoid talking or moving.
Your Results
Your results are available immediately. Steve prints your metabolic profile on the spot and walks you through every metric: your resting energy expenditure in calories, the ratio of fat to carbohydrate your body is using for fuel, and your mitochondrial efficiency. This is a full interpretation and education session, not just a printout.
Next Steps
Your ECAL results provide a precise foundation for nutrition and training decisions. If further guidance would help, Steve can prepare a referral to a dietitian, nutritionist, or medical professional based on your results.
What Can AFFECT RESULTS
Even with proper preparation, several factors can influence your resting metabolic rate from one test to the next. Understanding these helps you interpret your results in context.
Illness and infection
Your body increases energy expenditure when fighting off illness. Even a mild cold can elevate your resting metabolic rate above its true baseline. If you are unwell, consider rescheduling.
Nicotine
Nicotine is a metabolic stimulant. Smoking, vaping, or using nicotine patches or gum before your test will elevate your resting energy expenditure and distort your results. Avoid all nicotine products for at least 12 hours before your appointment.
Stress and sleep quality
Chronic stress elevates cortisol, which can influence how your body metabolises fuel at rest. Significant sleep disruption may have a similar effect, though the evidence is less direct. Where possible, test under consistent conditions.
Hormonal fluctuations
Menstrual cycle phase can influence resting metabolic rate. Research shows a small increase during the luteal phase, typically 3 to 5%. Thyroid function also plays a direct role. These are not reasons to avoid testing, but they are worth noting when comparing results across different time points.
Medications
Some medications affect metabolic rate directly. Beta blockers, thyroid medications, stimulant medications, and corticosteroids can all shift your resting energy expenditure. Continue taking them as prescribed, but let Steve know what you are on so your results can be interpreted accurately.
Ambient temperature
If you arrive very cold or overheated, your body may still be expending energy on thermoregulation. The Scan-Van is climate controlled, but the effects of extreme outdoor conditions can carry over briefly.
Clinical SAFETY and Suitability
The ECAL metabolic test is non-invasive and safe for virtually everyone.
No Electrical Current
Unlike bioelectrical impedance devices, the ECAL does not pass any current through your body. It measures only the gases you breathe. This means there are no contraindications related to pacemakers, defibrillators, or other implanted electronic devices. If you have an implant of any kind, the ECAL test is completely unaffected.
Pregnancy
The ECAL test is safe during pregnancy. It involves nothing more than breathing through a mouthpiece while seated. There is no radiation, no electrical signal, and no physical contact beyond the mouthpiece and nose clip.
Respiratory Considerations
The test requires breathing through a mouthpiece with a nose clip for 5 to 8 minutes. If you have a respiratory condition such as asthma, COPD, or significant nasal obstruction, let Steve know when you book. Most respiratory conditions do not prevent testing, but Steve may need to adjust the setup or timing to ensure you are comfortable and your results are reliable.
Preparing for ECAL FAQ
What does the ECAL test measure?
The ECAL is an indirect calorimeter. It measures the volume and composition of the air you breathe in and out, including oxygen consumption, carbon dioxide production, flow rate, and ventilation. From this data it calculates your resting energy expenditure in calories, the ratio of fat to carbohydrate your body is burning for fuel at rest, and your mitochondrial efficiency. It provides a complete picture of how your metabolism is functioning, not just a single calorie number. For a deeper look at the technology, visit the About ECAL page.
How long does the ECAL test take?
The breathing component takes approximately 5 to 8 minutes. Allowing for additional time for setup, results interpretation, and your education session with Steve, we normally expect your appointment to take 30-40 minutes.
Is the test uncomfortable?
No. You sit or recline in a comfortable position and breathe normally through a mouthpiece with a nose clip. The mouthpiece may feel unfamiliar for the first few seconds, but most people settle in quickly. There is no pain, no electrical current, and no physical discomfort.
Can I do an ECAL test and an InBody 970 scan at the same appointment?
Yes. Most clients book both together. The preparation protocols overlap, with one key difference: if booking both, minimise your water intake for the final 2 to 3 hours before your appointment, as fluid levels affect InBody body composition measurements. Review the Preparing for InBody guide for the full protocol.
Do I need a referral to book an ECAL test?
No. ECAL testing is available to everyone. No referral, no membership, and no prior testing history required. You can book directly through the Get Scanned website.
How often should I repeat the test?
That depends on your goals. If you are actively adjusting your nutrition or training, retesting every 4 to 6 weeks gives you enough time to see measurable metabolic changes. If you are tracking long-term trends, testing every 3 to 6 months is a reasonable interval.
What do I get after the test?
You receive a printed metabolic profile report on the spot. Steve walks you through every result in a full interpretation and education session. If your results indicate that further support from a dietitian, nutritionist, or medical professional would be beneficial, Steve can prepare a referral.
Is the ECAL test safe during pregnancy?
Yes. The test involves breathing through a mouthpiece while seated. There is no radiation, no electrical current, and no contact with your body beyond the mouthpiece and nose clip.