Yes and no, which can be a matter of perspective.
This is a fairly popular paper on spot reduction,
(@belosol has already referenced this but I want to expand on it.)
Lyle McDonald wrote a pertinent view on this paper. Quoting him,
based on the measured changes in blood flow and lipolysis, the researchers estimate that, in 30 minutes of local exercise, an additional .6-2.1 milligrams (one milligram is one thousandth of a gram) per 100 grams of adipose tissue adjacent to contracting muscle was mobilized.
Let me put that in context. First let’s assume that you’re carying a whopping 5 kg (11.1 pounds) of fat in a specific area.
If local exercise can mobilize 0.6-2.1 milligrams of fat per 100 grams of fat mass, that works out to:
0.6-2.1 mg/100 grams * 1000 grams/kg * 5 kg = 30-105 milligrams of fat.
Or 0.03-0.1 gram of extra fat mobilized in 30 minutes of activity.
Now, a single pound of fat (0.454 kg) contains about 400 grams of fat so our hypothetical 11.1 pounds of fat contains 4,440 grams of fat. And 30 minutes of local activity mobilized at most 0.1 gram of fat. Whoo hoo. You’ll be ripped in about 1000 years.
To take it even further, there are 48, 30 minute intervals in a day.
So, if you were to wear an EMS device on the stomach all day you would (theoretically) burn 4.8 grams of fat in that area (48 * 0.1).
4.8 grams is 0.01 pounds.
Thus,
- After 10 days you'd burn 0.1 pounds
- After 100 days you'd burn 1 pound
If you only wore the device half the time, then you'd double the amount of days.
200 days to burn 1 pound of fat, while having to wear something on your stomach 12 hours a day?
Point being, practical considerations will trump the theory.
Important general point
This if often the case with exercise science, and nutrition, trends / gimmicks / research.
I distinctly remember around the time this paper on spot reduction was published green tea being a huge "it" supplement, due to fat loss properties. If you read a little though, you'd find green tea could help burn more fat...an extra 80 calories a day.
Hey, we often want fat-loss clients to have a longterm point of view, but worrying about 80 calories is excessive.
With nutrition, you'll often come across statements like "eating broccoli decreases one’s chances of getting cancer by 50%," and say you and your friend both have a 1% chance of getting cancer but your friend eats a lot of broccoli.
Thus, your friend’s chance of getting cancer is .5%, or half of yours.
Great…at the end of the day you still only have a 1% chance of getting cancer and your friend only a .5%. (This is also referred to as absolute versus relative risk.)
In the weight-loss world, 99% of what you'll read may have nuggets of truth behind them, but in practical terms are all but useless to the everyday person. Whether that be due to implausibility of implementation or the average person not caring about a half a percent difference.
It can be interesting to learn about, but if one is trying to lose weight, time and energy is much better utilized on cooking at home and getting some exercise.