Note to non-UK readers: the "trainers" mentioned in the report refer to shoes, not personal trainers. That's British English for sports shoes.
I read the report and it says some good things but implies some bad things.
First of all, yes, most sports drinks, supplements, and shoes won't help the average fitness person who frankly isn't likely working hard enough to begin with for any of that to matter. People who are walking 30 minutes 3x a week on a treadmill, for example, shouldn't be taking carb drinks or wearing special shoes because they likely don't need them.
And yes, the effects of these accessories is sometimes overblown.
But for people that are seriously into fitness (way beyond the BBC's usual readership), these things can make a difference. For example, for really long, intense workouts, water isn't going to be enough. You'll lose too many electrolytes, especially in summer and you could likely benefit from the inclusion of carbs to fuel the workout.
Supplements are useful too but only in this order IMO: 1. fitness, 2. nutrition, 3. supplements.
If the fitness regimen is solid (it usually is not), and the nutrition you get from food has been addressed (this is even rarer), then supplements can be useful. They aren't just "expensive milk" as the article suggests.
Take for example whey protein. If you're on a heavy weightlifting regimen and need lots of protein, it can be tough to get that much from meat, etc. alone. It's cheaper, more efficient, and more convenient to supplement with whey protein. And the calorie count would also be lower.
Shoes depend on how much you exercise and what type you're doing. Running pounds the body and a good pair of shoes can make all the difference. Olympic lifting demands that you have a certain type of shoe for stability or you will court an injury. In these cases, normal shoes just won't work. Now that doesn't mean all the bells and whistles in the ads are justified. They aren't. But companies are just using marketing to sell their products.
Finally, I'd like to point out that the lack of "evidence" in a lab really means nothing. Studies are incredibly flawed and rarely show anything that improves real world results. That doesn't matter. Trainers and coaches are the mad scientists and the gym is their lab. They are paid to get results and the good ones do or their kids wouldn't eat. But in the last 20 years or so, science has heavily criticized them for not proving that these things work to the scientists satisfaction.
Fortunately the pendulum is starting to swing the other way. Folks are looking more to those that actually get results and can prove it through testimonials of other clients that have gotten results. What does or doesn't happen in a petri dish is irrelevant.
This is a good post from Arnold Schwarzenegger's new blog explaining this phenomena:
http://www.schwarzenegger.com/fitness/p ... -new-again
Hope that helps.