昨晚，我在看电影《仍然爱丽丝(Alice)》 ，我看到其中一位演员戴着Jawbone UP设备。这对我来说是新事物，它表明可穿戴设备正在缓慢但肯定会变得司空见惯。最近，很多人问我“我应该得到什么？” 没有清楚地了解这些设备如何改善他们的生活。嗯……(Well… one)购买可穿戴设备的一个很好的理由是帮助你减肥。在本文中，我将分享如何将可穿戴设备与MyFitnessPal应用程序结合使用，以跟踪您的卡路里不足(calorie deficit)并实际减肥。
我应该买哪种可穿戴设备？
第一(First)件事。并非每种工具都适用于每种类型的工作。这包括可穿戴设备。虽然它们中的大多数被宣传为可用于跟踪锻炼、跟踪睡眠和从这些数据中获得洞察力，但事实却更加微妙。造成这种情况的主要原因是，作为一家可穿戴公司，用一个设备做这么多事情需要付出巨大的努力：
- 制造设备、销售并大规模生产
- 创建(Create)Web 和移动应用程序以查看您的数据
- (Implement)在数据之上实施洞察引擎
- 处理物流以将其运送到世界各地
- (Create)为其他开发人员创建API（应用程序可编程接口）以在其上构建应用程序
- 拥有一个用户社区并维护该社区
- 查找其可穿戴设备的真实用例
- 而这样的例子不胜枚举…
由于大多数可穿戴设备都是由少于 50 人的初创公司和团队开发的，因此用很少的资源做很多事情是一项巨大的努力。这就是为什么在实践中，上面列表中只有一些事情做得很好，而其他事情还有很大的改进空间。此外，由于可穿戴设备行业存在严重的参与度问题(engagement problem)（很大一部分用户在几个月后停止使用它们），他们必须继续做所有事情，因为他们不知道参与失败的原因。这样做的一个直接后果是所有可穿戴数据都是不准确的。不要期望在绝对水平上完美地计算步数。事实上，你甚至不需要那个。您需要的是一个数字，当您的行为有所改善时，该数字会有所改善，以便您知道该数字何时更高，您正在做正确的事情。由于大多数可穿戴设备只包含加速度计，因此在某些情况下（例如骑自行车或举重）(cycling or weight lifting)卡路里燃烧估计可能是错误的(calorie burn estimation). 在这些情况下，您的身体会在不移动的情况下做出很大的努力，但加速度计无法轻易检测到这一点。这就是为什么可穿戴设备制造商提供手动输入这些活动并计算这些锻炼的方法。这增加了最终用户的障碍，使使用设备变得相当复杂。大多数可穿戴设备都有一个有趣的错误，那就是将驾驶视为一种锻炼。我看过客服(customer service)回复甚至建议使用允许他们排除开车时间的特殊功能。严重地？我必须记得我什么时候开车从计算中排除这种情况？这就是为什么根据您的目标（改善睡眠、减轻体重、变得更加活跃等），您应该选择该类别中最好的可穿戴设备。现在，您将接受它在其他领域不发光的事实。我的理论是，随着可穿戴设备的用例变得越来越明显（除了企业健康），这些设备将变得更加专业化。
什么是卡路里赤字？
通俗的讲，“卡路里赤字(calorie deficit)”就是一个人燃烧的卡路里和一个人摄入的卡路里之间的差值。我们燃烧卡路里有几个原因，主要原因是保持身体温度恒定(temperature constant)并保持重要器官的功能。这是由BMR(BMR)或基础代谢率(Basal Metabolic Rate)来衡量的。一个人摄入的卡路里量是通过将各种食物的卡路里数相加来确定的。食物(Food)被转换为能量测量单位，以便能够对(energy measurement unit)能量平衡(energy balance)进行高级概述. 然而，并非所有的卡路里都是一样的，不同类型的大量营养素会使身体表现不同。常识是 3500 大卡相当于 1 磅（0.45 公斤）的脂肪。但是，请注意，如果您开始挖掘这个事实(start digging this fact up)，您可能会惊讶于其背后缺乏科学依据。所以，如果人体是一个热力学系统，你只需要少喂它 3500 大卡，然后耐心地等待那一磅脂肪脱落。这就是为什么卡路里不足的概念(calorie deficit concept)对减肥如此重要的原因。同时，它具有高度误导性：3500 kcal 的配方适用于 1 磅由 87 % fat和 13 % water和瘦肉组织组成的肉。但由于测量体脂本身就是一门黑魔法(measuring bodyfat is a black art in itself)，你永远不会知道你在体重秤上看到的实际上是由于失去了脂肪还是(fat or something)其他原因（例如脱水）。除了使用体重秤外，您还可以测量腹部以确认您的趋势良好并且您很快就会需要新衣服🙂这些原因使整个卡路里计算(calorie computation)相当近似。此外，人们常常忘记卡路里不足(calorie deficit)是两个量之间的差异。因此，您可以控制其中一个或两个以获得更大的差异。身体活动与你吃的东西一样重要，这就是为什么有一种方法来估计你燃烧的卡路里很重要。这就是可穿戴设备的用武之地。
可穿戴(Do Wearable) 设备(Devices) 如何估算(Estimate) 燃烧的(Burned)卡路里(Calories) ？
市场上的大多数可穿戴设备都可以估算燃烧的卡路里。它们通常只包含一个加速度计，它们的计算是基于人在BMR上的步数。乍一看，这似乎是遥不可及的。在实践中，我发现它非常好，原因如下：
- 首先，对于一个普通人来说，“适度燃烧的卡路里”的数量与步数高度相关。下面是我的一个Programmer Fitness客户的实际图表。这是一个人在短期内通过做某事可以实际控制的最大燃烧卡路里量。从长远来看，可以通过增加更多的肌肉质量来增加(muscle mass)BMR。然而，这需要相当多的工作和更严格的饮食(stricter diet)。
- 其次，我们大多数人并没有真正定期锻炼，所以整天四处走动确实是我们燃烧这些卡路里的方法。
如何将可穿戴设备连接到MyFitnessPal以查看卡路里赤字(Calorie Deficit)？
让我们假设您已经决定了哪种可穿戴设备适合您的需求和生活方式并且您购买了它。下一步是将其连接到MyFitnessPal以跟踪您的卡路里不足(calorie deficit)。我将展示它是如何为Jawbone UP24完成的。该过程与其他类型的设备类似。在MyFitnessPal应用程序的主菜单中，转到应用程序和设备(Apps & Devices)。
然后，您从列表中选择您自己的设备。
接下来，您将看到一个确认屏幕(confirmation screen)。点击连接(Connect)。
这会将您转到设备 Web 应用程序的登录页面。输入(Enter)您的凭据。
登录后，您必须授予MyFitnessPal足够的权限，以便它可以读取您的可穿戴设备收集的数据。点击是(Yes)。
成功完成后，在几个小时内，您设备的步数将显示在MyFitnessPal应用程序的主屏幕上。
通过运动燃烧的卡路里将自动计入您的每日卡路里赤字(calorie deficit)。
在支持的设备列表中，我们拥有市场上大多数新的可穿戴设备。它还支持RunKeeper或Endomondo等应用程序，它们可以使用智能手机的(Endomondo)加速度计和 GPS(accelerometer and GPS)跟踪您的锻炼情况。如果您是一家初创公司，并且希望您的设备出现在该列表中，那么有些事情告诉我您必须在MyFitnessPal上向合适的人介绍一些内容。但我想这很正常。
什么是好的卡路里赤字？
当您试图以可控的方式减肥或增重(weight or gain weight)时，这是您必须回答的最棘手的问题，也称为“增重”。在我看来，最好的价值是你可以舒适地生活的价值，而不会对你的生活方式做出重大的、突然的改变。根据我自己的减肥经验(loss experience)，较小的变化往往更可持续，所以唯一的问题是要做出哪些改变才能使它们既小又有效。如果您想确定卡路里不足(calorie deficit)的上限，这篇科学文章(this scientific article)建议每天每磅（0.45 千克）体脂的最大(body fat)卡路里不足(calorie deficit)为 10 大卡。为了知道多少磅你有身体脂肪(body fat)，你必须知道你的身体脂肪(body fat)百分比。无需离开家或购买任何东西(home or buying anything)即可进行估算的最简单方法是查看一系列图片并将自己与这些图片进行比较。对于大多数人来说，卡路里不足的最终上限是(calorie deficit)每天(upper bound)500 到 1000 大卡之间。但请记住，我们总是对自己的目标过于雄心勃勃。从长远来看，保持它们小而可持续总是更好。
结论
在本文中，我定义了卡路里赤字(Calorie Deficit)的概念，并解释了为什么它是减肥难题(weight loss puzzle)中的核心部分。我已经分享了如何将可穿戴设备连接到MyFitnessPal ，这样您就可以在(MyFitnessPal)卡路里不足的计算(calorie deficit computation)中整天四处走动。在研究了很多减肥相关的资料后，很明显一切都是近似的。通过卡路里、步数或任何其他指标来量化体重减轻，并没有预测确切最终结果的目的(end result). 相反，它允许您将日常模式分解为可量化的结果，并确定您可以轻松改进并产生巨大影响的地方。最后但并非最不重要的一点是，请确保您不要沉迷于卡路里不足(calorie deficit)本身。既然您已经准备好卡路里计数器(calorie counter)和精美的可穿戴设备，请不要忘记多吃健康食品和少吃加工食品。这个世界上没有一个单一的数字来量化你所吃食物的质量，你有责任慢慢养成更健康的习惯。从长远来看，您将受益于这些，而不是痴迷于秤上的每一磅。
Andrei Ismail 是一位经验丰富的软件工程师，拥有创业经验和人工智能博士学位。他在 6 个月内减掉了 50 磅，目前正在为极客制定健身教练计划，可在WEIGHT LOSS FOR ENGINEERS获得。(Andrei Ismail is an experienced software engineer with startup experience under his belt and a PhD in Artificial Intelligence. He has lost 50 pounds in 6 months and is currently working on a fitness coaching program for geeks, available at WEIGHT LOSS FOR ENGINEERS.)
How To Use MyFitnessPal & A Wearable Device To Track Your Calorie Deficit
Last evening, I was watching the movie Still Alice and I saw one of the actors wearing a Jawbone UP device. This is new for me and it signals that wearables are slowly but surely becoming commonplace. Lately, many people ask me "what should I get?" without having a clear idea on how these devices can improve their life. Well… one good reason to buy a wearable is to help you lose weight. In this article, I will share how to use a wearable device in conjunction with the MyFitnessPal app, in order to track your calorie deficit and actually lose weight.
Which Wearable Device Should I Get?
First things first. Not every tool is good for every type of job. And that includes wearable devices. While most of them are being marketed as useful for tracking workouts, tracking sleep and gaining insights from that data, the truth is more nuanced. The main cause for that is that, as a wearable company, it's an enormous effort to do so many things with one device:
- Create the device, market it and produce it on large scale
- Create an web and mobile application to view your data
- Implement an insights engine on top of the data
- Handle the logistics to ship it around the world
- Create an API (application programmable interface) for other developers to build applications on
- Have a community of users and maintain that community
- Find real-life use-cases of their wearable device
- And the list goes on…
Since most wearables are developed by startups and teams smaller than 50 people, it is a huge effort to do so many things with so few resources. That is why, in practice, it turns out that only some of the things in the list above are done properly, while others have plenty of room for improvement. Moreover, since the wearables industry has an acute engagement problem (a large percentage of the users stop using them after a few months), they have to keep doing everything because they do not know the cause of the engagement failure. One immediate consequence of this is that all wearable data is inaccurate. Don't expect steps to be counted perfectly on an absolute level. In fact, you don't even need that. What you need is a number that improves when your behavior improves, so that you know when that number is higher, you are doing the right thing. Since most wearables only pack an accelerometer, the calorie burn estimation can be wrong in certain situations such as cycling or weight lifting. In those situations, your body is making a big effort without moving around, but that cannot be detected easily with the accelerometer. That's why the makers of wearable devices offer ways to manually enter those activities and account for those workouts. That raises the barrier for the end-user, making it quite complicated to use a device. One amusing bug that most wearables have is counting driving as a workout. I have seen customer service replies that go as far as suggesting to use a special feature that allows them to rule out periods when they were driving. Seriously? I have to remember when I was driving to rule that out from the computation? This is why, depending on your goal (improve sleep, lose weight, become more active, etc.), you should choose the wearable that is the best in that given category. For now, you will have accepted the fact that it doesn't shine in the other areas. My theory is that as use-cases for wearables become more and more apparent (besides corporate wellness), the devices will become more specialized.
What Is The Calorie Deficit?
In layman's words, the "calorie deficit" is the difference between the calories burned by a person and the calories eaten by a person. We burn calories for several reasons, the main reason being to keep the body's temperature constant and to keep the vital organs functioning. That is measured by the BMR, or the Basal Metabolic Rate. The amount of calories eaten by a person is determined by adding up the number of calories of the individual foods. Food is converted into an energy measurement unit for the purpose of being able to have a high-level overview of the energy balance. However, not all calories are created equal, and different types of macronutrients make the body behave differently. Common wisdom is that 3500 kcal is equivalent to 1 pound (0.45 kg) of fat. However, beware that if you start digging this fact up, you might be surprised at the lack of scientific basis behind it. So, if the human body acts as a thermodynamical system, you just need to feed it 3500 kcal less and patiently wait for that pound of fat to come off. That is why the calorie deficit concept is so central to weight loss. At the same time, it is highly misleading: the 3500 kcal formula holds for 1 pound of flesh comprised of 87% fat and 13% water and lean tissue. But since measuring bodyfat is a black art in itself, you will never know if what you see on the scale is actually due to lost fat or something else (such as becoming dehydrated). In addition to using the scale, you can take belly measurements to confirm that you are on a good trend and that you will soon need new clothes 🙂 These reasons make the whole calorie computation rather approximate. Moreover, people forget all too often that calorie deficit is the difference between two quantities. So you can control one or both of them to obtain a bigger difference. Physical activity is just as important as what you eat, and that is why it is important to have a way of estimating your calories burned. This is where wearable devices come in.
How Do Wearable Devices Estimate Calories Burned?
Most wearable devices on the market offer an estimation of the calories burned. They usually contain only an accelerometer and their computation is based on the number of steps that the person does on top of the BMR. At first sight, this seems to be way off. In practice, I have found it to be quite good, for several reasons:
- First, for a regular person, the number of "moderately burned calories" is highly correlated with the number of steps. See below for an actual graph from one of my Programmer Fitness clients. This is the largest amount of burned calories that the person can actually control by doing something on the short term. The BMR can be increased on the longer term by adding more muscle mass. However, that requires quite a bit of work and a stricter diet.
- Second, most of us don't really work out regularly, so moving around all day long is really what we do to burn those calories.
How Do You Connect Your Wearable Device To MyFitnessPal To See The Calorie Deficit?
Let's assume that you've decided which wearable device fits your needs and lifestyle and you bought it. The next step is to connect it to MyFitnessPal in order to track your calorie deficit. I am going to show how it's done for the Jawbone UP24. The process is similar for other types of devices. In the main menu of the MyFitnessPal app, go to Apps & Devices.
Then, you select your own device from the list.
Next, you will be presented with a confirmation screen. Tap Connect.
This will send you to the login page of your device's web application. Enter your credentials.
Once you log in, you will have to grant MyFitnessPal enough permissions so that it can read the data collected by your wearable device. Tap Yes.
Once you complete that successfully, within a few hours, the number of steps from your device will be shown on the main screen of the MyFitnessPal application.
The calories burned through exercise will count towards your daily calorie deficit, automatically.
Among the list of supported devices, we have most of the new wearables on the market. It also supports applications such as RunKeeper or Endomondo, which can track your workouts with your smartphone's accelerometer and GPS. If you are a startup and you want your device up there in that list, something tells me you have to get some introductions to the right people at MyFitnessPal. But I guess that's normal.
What Is A Good Calorie Deficit?
That's the single toughest question that you have to answer when you are trying to lose weight or gain weight in a controlled way, also known as "bulking up". In my opinion, the best value is the value you can live with comfortably, without making major, abrupt changes to your lifestyle. From my own weight loss experience, smaller changes tend to be more sustainable, so the only question is which changes to make so that they are both small and impactful. If you want an upper limit for what your calorie deficit should be, this scientific article recommends a maximum calorie deficit of 10 kcal per pound (0.45 kg) of body fat per day. In order to know how many pounds of body fat you have, you have to know your body fat percent. The easiest way to estimate without leaving home or buying anything is to look at a series of pictures and compare yourself to those. For most people, the final upper bound for the calorie deficit is somewhere between 500 and 1000 kcal per day. But remember, we always tend to be over-ambitious about our goals. Keeping them small and sustainable is always better on the longer term.
Conclusions
In this article, I have defined the concept of Calorie Deficit and explained why it is such a central piece in the weight loss puzzle. I have shared how to connect a wearable device to MyFitnessPal so that you get credit for moving around all day long in your calorie deficit computation. After studying a lot of weight loss related material, it's quite obvious that everything is an approximation. And quantifying weight loss via calories, steps or any other metric, does not have the purpose of predicting the exact end result. Rather, it allows you to break down your daily patterns into quantifiable results and pinpoint where you can easily improve with a large impact. Last but not least, make sure that you do not obsess about the calorie deficit itself. Now that you're all setup with the calorie counter and your fancy wearable device, don't forget to eat more healthy and fewer processed foods. There is no single number in this world to quantify the quality of the food that you eat and it's your responsibility to slowly build healthier habits. On the long term, you will benefit from those much more than from obsessing about every pound on the scale.
Andrei Ismail is an experienced software engineer with startup experience under his belt and a PhD in Artificial Intelligence. He has lost 50 pounds in 6 months and is currently working on a fitness coaching program for geeks, available at WEIGHT LOSS FOR ENGINEERS.
