The New Year has come around again, the time every year when we realise that our indulgences over the festive period have caught-up with us. But fear not, because thanks to the start of the New Year we now have the motivation to up our game and abide to the boring diet and training regimes that we pay expensive PT’s and nutritional gurus to set us!

Maybe I am being rather cynical, or just honest, as I often have the best intensions and pay for the ‘best’ advice, yet still seem to go off kilter come the cold and dark days of February (note I didn’t say Jan, as I can keep it up for at least a month!) when although I can notice the signs of change, I am still not completely convinced that the expensive diet/training plan is working for me.

Fear not if you have the same concerns, as there are numerous products on the market now that enable you to assess your nutritional intake and body composition, in addition to the trusted weight scales. Whilst a lot of these products have been available for a while, their sophistication has increased markedly over the past few years warranting a further look. Luckily for you I have conducted research on your behalf, on the new scientific information that has been made available relating to products that purport to help maintain and monitor your body fat levels and or nutritional intake. I have narrowed my research to three products, one that is accessible to all regardless of your skill level, the next is a slightly more sophisticated piece of equipment and available at most gyms or pharmacies, and lastly the most accurately available method to the general public.

But first you need to understand all the scientific or sometimes pseudo-scientific jargon that PT’s, nutritionist, websites and apps use to guide/confuse us. There are too many to discuss them all in this feature article, but I will explain the main acronyms and their meaning as they are actually rather useful! Basal Metabolic Rate (BMR) (sometimes referred to as Resting MR) is is a measure of the amount of energy required to maintain normal bodily functions. Most apps workout your BMR through you inputting your gender, height and weight, but luckily I will give you the formula so you can work it out for yourself: there are numerous calculations that are used in scientific research but the most popular is the Scofield’s equation which is: for men = 11.4 X Kg weight + 873.1 and for women = 8.1 X Kg weight + 845.6 remember this will give you your BMR, thus giving you your base level (this will help for understanding the minimum calories you need to maintain your health while losing body fat). From this starting point the results are multiplied by a figure dependant on level of physical activity (e.g. both genders multiply by 1.3 for sedentary activity and 1.7 for men and 1.6 for women who are lightly active etc. full details available on my web page). These equations will guide you towards your weight loss goals through tweaking your diet accordingly using the basic negative/ positive energy balance technique! If I need to explain what the aforementioned energy balance equation is, then I may as well give-up now!

Another important acronym used is Body Mass Index (BMI) this is a measure used to categorise health based on weight and height (measures in fig.1): Body mass (kg) / height m2. This may not be the most scientific and accurate measure but it is still used in insurance, health centres etc. Fig 1 shows the ranges.

As we are all looking to lose body weight, body fat percentage is an important gauge but what is it? Well it’s something that we can never fully know (unless you are dead and a full analysis of your whole body can be done, this is extreme, even for bodybuilders!), but we can estimate. Terms used are Fat Free Mass (FFM) which is calculated as [body mass – fat mass] and Lean Body Mass (LBM) which is the combined weight of the internal organs, bones, muscles, water, ligaments and tendons, minus fat.

Now that the jargon is out of the way let’s look at the rationale behind the three products chosen, the readily available smart phone health applications (apps) that enable you to monitor your dietary intake of carbohydrate, protein and fat and thus calculate your calorie intake (although this is dependent on the accuracy of information you provide!), and work out calorie expenditure through daily activity and exercise duration. The second device is slightly more specialised and is available in most gyms or pharmacies, Bioelectrical Impedance Analysis (BIA), I know it’s a mouthful but it is a useful tool for monitoring body fat percentage. Lastly, Air-Displacement Plethysmography (ADP) this is not available at most of your local gyms but it is the gold standard in body fat composition machines for the general public and is used in scientific research and for serious athletes, I have used this as a litmus test to compare the BIA to understand whether it is an accurate measure or not.

Smart phones applications (APPs), these are the most accessible and self-explanatory bits of tech kit available to monitor what we eat and drink and to gain an understanding of the amount of activity we do each day. I myself use an app, and monitor my activity level, usually competing against friends, secretly trying to log more activity than them (although I never strap my phone to my dog while we are playing fetch!!), therefore I understand the motivational benefits of the app. However, does scientific research agree with my anecdotal evidence of this motivation, it would appear that it does, albeit using a stricter criterium.

The scientific research referred to the fact that apps engage behavioural change techniques (BCTs) (theory-based method for changing one or several psychological determinants of behaviour such as a persons’ attitude), reinforcing positive behaviour in the form of physical activity and dietary changes as a result of their use. This seems to be echoed by numerous studies suggesting that using a app can be a useful tool in making eating and lifestyle changes.

Whilst these studies were very positive, and provide evidence that BCTs were effective with regard to initial weight loss and also support continued efforts to maintain lifestyle changes associated with weight management, they did not evidence that education and understanding of nutritional information increased. This poses a problem as the research suggests that although the apps do help people with their goal of weight loss/management their understanding of nutrition does not increase significantly therefore are people just relying on the app without consciously thinking about why they are eating what they are eating? This is an interesting observation!

If you are thinking about downloading an app then ensure that it includes features such as an activity monitor and a diet planning facility as well as notifications when you achieve certain activity levels. With your increased level of awareness, you can maintain your new nutritional and physical regime without the need to go to weight watchers! (that has to be a good thing!)

Bioelectrical Impedance Analysis (BIA) sounds rather daunting, however it is basically a machine that you stand on in your bare feet and grasp handles with your hands, this enables electrical impulses to move through your body, the speed at which the impulse travels determine your body fat level, as the electrical impulses run faster through muscle tissue than fat, i.e. the faster the impulse the leaner you are.

There have been numerous scientific research papers determining the validity of the BIA measure, I would like to note that the tests were conducted on commercial machines such as the TANITA 310 and the TANITA BF-689 (and not the machines you can pick-up from Aldi!). Most gyms have commercial machines available and the quality of these are very good therefore I wouldn’t recommend rushing out to purchase a ‘body-fat percentage scale’ as it may not be that accurate, although you must remember that even the commercial scales provide an estimate and can never be totally accurate.

The scientific literature suggests that this is a viable way to estimate your body fat percentage and that monitoring your body fat is an effective way to stay motivated and continue to adhere to your new dietary and training regime. Certainly, in comparison to other methods of body fat estimates like callipers, (if you are not familiar with this old school technique which is still used today by practitioners then this and all the other methods of determining body composition can be found on my website), this is a quick and accurate estimate without requiring any prior knowledge or skill, (older methods are only as accurate as the practitioner performing the estimate), and provides a readout of information that can be monitored habitually to note any changes thus helping to continually motivate. The most interesting research in the validity of this technique is the comparison with the AirDisplacement Plethysmography technique, where surprisingly it is shown that BIA measures are relatively comparable therefore proving that the BIA machines are a viable technique for monitoring body composition. Naturally when taking the estimate, you should consider the time of day, your food consumption etc and try to emulate the same conditions each time to ensure accurate comparable results.

Therefore, I would recommend regularly (once a week) using the BIA scales at your gym (or pharmacy if your gym is ‘Old School’), this will provide motivation for continued progress and maintenance of your new regime. This will provide enough information to enable you to monitor your body composition rather than merely your weight which often can be a little misleading due to the combination of training you may be adding lean mass whilst still dropping fat!

Finally, “Is Air-Displacement Plethysmography (ADP) the gold standard method of body composition analysis for the general public?” This test is usually performed in a ‘BOD Pod’ where you sit in a chamber wearing as little as possible (you even have to wear a swimming hat!), the chamber measures the air displaced and the results indicate body density, from this data body composition is calculated.

This method is the most accurate method available to most individuals, (there are more extreme estimates that are very expensive like dual-energy X-ray absorptiometry (DXA)), as some health centres and specialist fitness testing facilities have ‘BOD Pods’. Readings can be expensive but not restrictive at around £40-60 per reading. This will give the most accurate indication of body composition and could be used once or twice a year to ensure your other methods of data gathering are accurate.

Again, as this is the gold standard it would only really be used for individuals who are very serious about weight loss and not necessarily for recreational athletes as regular trips to the BOD pod can become very expensive and are not really needed with other methods of measurement being relatively accurate. To conclude I would suggest that the scientific literature available although limited due to the continued innovation of the smart phone, indicates that the apps used by individuals do provide added motivation to help lose and maintain weight loss plus these apps are free (at least the basic ones, some work better with a band which can be expensive). The available literature also evidences that BIA is reliable (contrary to my personal observations) and is almost on par with the more expensive ADP thus giving another motivational tool to use for the health-conscious individual. Use of BIA in many Gyms is free with pharmacies charging between 50p and £1 which is reasonable for once per week. This seems certainly less expensive than joining weight watchers, which costs around £6.25 per meeting plus initial registration costs of £10.70 and online membership £12.95. Although you may miss getting your peers to judge you on your weekly weight and food intake but on the positive side at Weight Watchers meetings you do get cake!

Of course, these methods of monitoring your progress post New Year’s resolution will not necessarily lead to dropping those pounds added over the festive period on their own. However, it will provide meaningful motivation and recognition that the dreaded nutritional and training regimes you have started are working and are worth persisting with!

Remember if your goal is to lose weight it doesn’t become reality through magic apps; it takes sweat, determination and hard work!


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