You are probably hearing it more and more often that what you eat will help you further your fat loss goals more significantly than how often you work out.
"You can't out train a bad diet".
This is due to a number of reasons, including the fact that we burn far fewer calories than expected during a workout, and it’s incredibly easy to eat those calories right back after the gym. So is the 80% diet, 20% exercise really the way for fat loss?
Absolutely with no exceptions.
To lose 1lb (0.45kg), you need to achieve a 3,500-calorie deficit. If you’re following the 80/20 rule, you ideally want to burn about 750 calories through exercise within the week and the rest comes from dietary changes.
To put this whole 80/20 rule into perspective you would need to run about 7-10 miles a day (depending on the individual) to burn that 1lb of fat. This is, not time practical for most of us, the average person can’t keep up this pace without suffering injury and significantly increasing their caloric intake in order to fuel them through the run and this amount of running is not going to be helpful when your looking to get that toned look. Follow the link for why just cardio wont make you toned. The Secret To a Toned Look.
This doesn't mean you just cut out exercise it offers so many health benefits and if looking toned or putting on some serious muscle is the ultimate goal it is essential.