The other night, a friend told me that he was trying to spend more time taking cabs. This surprised me, because I happen to know this friend has a Fitbit, and that he's rather proud of how far he's walked under its watchful electronic eye. (I'm being polite: you never just "happen to know" that a friend has a Fitbit because they tell you on social media.)The Fitbit – if you've somehow managed to avoid this – is a little dingus that records how many steps you take in a day and allows you to compete with your friends for the most steps or to post the results to social media. Aficionados will happily march aimlessly up and down the hallway if it means narrowly edging out the next competitor on their leaderboard.So why was a step-counting devotee actively trying to walk less? "Look," he told me, "not all my shoes are comfortable. Some of them are really nice. If I walk too far in nice shoes, my feet hurt. So, I'm trying to take cabs."It might be the first time I've heard a Fitbit user say something akin to "I'm not going to walk more right now, because I don't want to."The Fitbit may have been the first tracker of its kind to go really big – though pedometers have been around for a while – but it has certainly many cousins. There are devices to track your sleep patterns (though Fitbits will do this as well), to keep an eye on your posture, to monitor your dog's activity levels, to analyze the fuel efficiency of your car or tweet your weight.Perhaps emboldened by this profusion of interest in data, last month a company called Mark One launched the Vessyl, a cup that analyzes the nutritional content of anything you put in it and tracks your sugar, caffeine, and water consumption. And the KGoal, touted as a "Fitbit for your vagina", is currently crowdfunding on Kickstarter. The latter device looks like a silicone hand grenade and is designed to record your progress as you do kegels, the exercise for pelvic floor muscles that women do to improve childbirth, continence and – most importantly, in my opinion – sexual pleasure. To emphasize that benefit, the KGoal even vibrates when you're doing your exercises right.Like the Fitbit, these newest health trackers don't come cheap; the Vessyl has a $99 promotional price and you can preorder a KGoal for $125, though the projected retail prices are $199 and $175, respectively. But, hey, how much is too much to spend to know that you're drinking a soda or clenching your vag?This stuff all sounds a bit silly, but I'm not enough of a curmudgeon to truly bemoan our national data fixation. It's often easier to understand what to do with data than to evaluate how you feel, and devices that can quantify your walking or blood pressure or vaginal strength let you take advantage of that. If spending $199 on a cup or $175 on a vagina grenade is the shortcut you need to generate and pay attention to your caloric intake and pelvic floor muscles, for instance, then godspeed.Plus, human brains respond directly to feedback about bodily functions: watching your heartbeat tracked on a monitor, for instance, gives you the ability to consciously slow them down with uncanny ease, through which you can eventually develop into a coping strategy for anxiety attacks and manage anger.Having access to biofeedback – real-time data about your body's functioning – has been shown to help people manage migraines, high blood pressure and even epileptic seizures. It is a powerful enough phenomenon that L Ron Hubbard essentially based a whole religion on it: Scientology's e-meter is a biofeedback device. And, in the 1940s, Dr Arnold Kegel invented a biofeedback device to help woman improve their pelvic floor muscle exercises and manage urinary control – an obvious precursor to the kGoal, and the very origin of the term "kegels".But the pitfall of data devices – and the external sharing of information that they encourage or require – is that they hijack your reward pathways. Instead of walking because it makes you feel good, or because it gets you out in the air or (my personal favorite reason) because sometimes there is bonkers stuff to see in between point A and point B, you walk in order to improve your stats. This sometimes means you walk even if it's a bad idea – if your shoes hurt, if you're not feeling well, if it's dangerously hot, if you're running late – because doing otherwise will mean a black mark on your record. Your stats will slide, and your stats (and the ability to brag about them on social media) are your reward.One friend tells me that, when her office did a step-counting competition, she was initially distressed because she couldn't adjust the pedometer's minimum "success" condition below 10,000 steps: she has fibromyalgia and isn't always up for that much walking every day. But, chastened by her colleagues' successes, she ended up trying valiantly to make the daily minimum – and subsequently spent at least one day per weekend asleep for most of the day, and had to take extra medication for pain in her legs and feet.The quantified self breaks down into numbers – and there's value to that – but it takes the aggregate self out of the equation. Focusing on the numbers our activities generate skips over how we feel and how we function – and it becomes really easy to forget about that entirely because neither figures in to your score.I'm a big fan of both walking and kegels (and I'm not genuinely worried that anyone is going to vaginacize herself into exhaustion). But I do have misgivings about the competitive psychological weirdness that piggybacks on genuinely valuable biofeedback.And it's not just weird for users, either: it's also frequently very weird for their social media pals. Many pedometers and other quantification tools are designed to be linked 龙卷风福彩3d胆码 to your Twitter or Facebook accounts, both to put pressure on users to keep going, and to promote the product (and to peer pressure) their friends. And while the KGoal isn't designed to tweet your results automatically, or even keep track of who's winning among your friends the way Fitbit can – thankfully – I honestly wouldn't be surprised if competitive types started sharing their kegel strength progress.All that biofeedback feedback can be oppressive – your friends are dragooned into the competition, at least as spectators, whether they want to participate or not – and it's boring as hell. I can absolutely understand the power of seeing yourself represented in numbers, but it's the height of narcissism to think that everyone else wants to stand there next to you and gaze at your data avatar.Still, I'm not interested in telling people to cast off their health-robot chains. Biofeedback data is too seductive to root out, and too valuable to really want to. So engineers, get at me: what we need is a quantified happiness tracker. Your stats improve when you walk to somewhere beautiful instead of marching in place at your desk, or use the KGoal purely for its vibration "rewards", or take a cab when your feet hurt.And every time you don't post the results to social media, the app gives you a big gold star.