Glad to have a fellow sly PT to bounce ideas off. Now dont take anything I say as a personal attack I'll admit its been known for me to be wrong on more then one occasion and im always willling to learn something new so I keep an open mind.
Now im not against interval training i have lots of clients do it for the reasons outlined in the article
Increased Aerobic Capacity – The amount of oxygen your body can use (oxygen uptake) is increased, so your overall aerobic capacity can increase faster than with just jogging
• Increased Lactate Threshold – Your ability to handle increased lactic acid buildup in your muscles substantially increases
• Improved Insulin Sensitivity – Your muscles more readily suck in glucose, instead of the glucose going to your fat stores
Do you have the links to those studies? The three links you provided just say high intensity training will burn more fat then slow steady state cardio and there's alot of pseudo science in a few paragraphs on those pages and provide no other science behind it other then 1 study of about 20 participants.
Its true about the the fat burning zone being a myth i.e it being 60-75 % of maximum heart rate, as VO2 max has no base on maximal fat burning zone but you can find out optimal fat burning zone by doing a VO2 max but the numbers are independent.
The last article is probably the best and most accurate and most well written so i'll focus on this. Many off the claims are correct but if you notice all the articles say is high intensity exercise will burn more calories after workout.
'As an added bonus, there’s also an “afterburn” effect known as EPOC (excess-post exercise oxygen consumption). You burn more calories for up to 24 hours after interval training, whereas going for a jog burns almost NO calories after'
Is this such a good thing? No one should be looking for weight loss but fat loss unless you're some crazy sportsman needing to drop lean weight for a weight class or something but 99 % of the general public want fat loss. Now if you train at a lower intensity using your aerobic system in your optimum fat burning zone you will burn fat but no calories after that. Thats great as those calories if your diet and training is correct can go towards building muscle. It is easily possible to build muscle and lose fat at the same time. I agree high intensity training is better for weight loss but not fat loss.
They make statements with no evidence to back it up
Yes, you burn more fat relative to glycogen when going for a walk, but what we care about is total fat burn. At higher intensities, you are burning far more fat, even though the fat/glycogen ratio is lower. In addition, Interval training allows you to exercise at very high intensities for a much longer period of time than steady state, so you burn more fat.
Higher intensities? If they mean interval training then how can this be? If you are doing this right you will be using your phosphogen system ATP/ ATP-CP. You burn ZERO fat in this high intensity. AS you know once you hit RQ1 you are burning 100% sugar (glycogen). After high intensity workout with your glycogen stores depleted you will burn more calories and yes from fat but you will also use amino acids i.e either the protein you est or more muscle tissue, pyruvic acid. Also if you are doing high intensity work properly how are you able to do it longer then slow steady state cardio? After a certain amount of time you are going to release cortisol and break down muscle, blunt testosterone production and blunt leptin production.
I would check out trainsmart
http://www.trainsmart.com/ these guys work with elite athletes and have literally thousands of case studies to back up their findings.
Im not saying im right or you're wrong we have different opinions on what works best which I think is great as it will keep scientific research thrusting forwarding and new things come along all the time, in 20 years probably be found out we were both wrong so i agree we'll have to agree to disagree lol