I don't know what it is, but lately I've been finding that clients I talk to are adding more and more into their training programs - doing at least one, if not two workouts per day. Which, in and of itself (and if properly managed) isn't a problem - if you're doing a multisport, such as triathlons or adventure racing, you'll know that there are extended periods of time where this is the norm. However, if you've had a good coach or program designer, you also understand that they have to be of varying intensities, and you have to organize the week so that you are working a variety of systems (regenerative, aerobic, high intensity conditioning, strength, etc).
However, that's not what I'm hearing about. More commonly, it's that they are coming into the gym and doing a moderate to high intensity resistance session 2x a week, running intervals 1-2x a week, and then doing some sort of home program nonsense like "Insanity" 2-4x per week on top of all that. And, not surprisingly, they're finding that they are plateauing, burning out or getting injured.
Like everything else, exercise is crucial to a healthy lifestyle - it's as important as everything else that fills the day, like work, family, friends, and so on. However, like these (and other) things, there is a tipping point - a place where it can become too much, and the returns begin to diminish. Or possibly, in a worst-case scenario, they may actually start to have the opposite effect. Unfortunately, what people tend to do in reaction to this stalling in their progress is to try and do more, adding another couple of "fat-burning" runs, or extra high-intensity sessions into their week... then become more and more frustrated by the lack of progress or decline in performance/results that become apparent.
I'm going to work from the assumption that if this describes you, you haven't spoken to your coach and been upfront about this - because if you have, and if you have a good coach, they would already have told you everything I'm writing about here. If not, then please keep this in mind:
More isn't always better.
Or an alternative example - almonds. Almonds are a powerful superfood, with plenty of positive attributes that contribute to your health: such as "good" fats, lowering sugar and insulin spikes in your blood after eating, to name a couple of examples. But this doesn't mean you can eat an endless amount every day. At some point, these benefits become outweighed by things like lack of variety, other missing nutrients and massive caloric overload.
So look back over your last few weeks of training, and consider the types and/or intensities that you've been working at... have you been eating almonds as part of a well-rounded nutritional plan, or eating bags and bags of nothing but?