Eduardo Diaz Sancha

When it comes to weight loss, let the fitness do the work. Where most folks go wrong 👇 "Couch dude" in the below example has really shitty metabolic fitness, i.e. fat-burning because, well, he spend a good chunk of his life on the couch. So, when he gets up and starts exercising at ~60% MHR he's only burning ~400kcal/hr. Worse than that, because of his shitty metabolic fitness, only 100 of that is coming from fat! Seeing this measly 400kcal/hr burn, couch dude does the math in his head and realizes he's only burning a cheeseburger. 1 whole hour for a cheeseburger?! Hell no! So, couch dude resolves to go harder and work out at 80% max HR, i.e. approaching threshold. Guess how many kcal are coming from fat now? Zero! That's right a big, fat, goose egg. So, couch dude is burning more kcal/hr but they're not coming from where he wants. They're not coming from fat! Worse than that... After couch dude is done with his hard workout his blood sugar is tanking because the whole thing was fueled with carbs. This makes him ravenous and he completely blows out his planned 500kcal deficit for the day and grabs 2 cheese burgers on the way home that completely offsets the 1 and a bit that he just burned. The long and the short of it... Couch-dude needs to slow the F down! He needs to start at the intensity that he actually is burning fat, even if that is, in the beginning, a tiny amount of energy expenditure. Then, as his base fitness builds, both the overall energy expenditure and the % of that expenditure coming from FAT will go up. But, it's only by initially slowing down that we turn couch-dude into a fat-burning machine! 🔥

Great Q from Tom... "How easy is too easy?" A few quick thoughts.... * There is metabolic benefit that comes from *very* easy movement for all. E.g. if I do a 45 min walk at 80bpm (~45% MHR), my blood lactate and blood glucose will reliably come down by a good amount following the "Zone 0" walk. This drop in blood lactate and blood glucose is accompanied by an increase in fat oxidation. This is a good thing! Metabolic fitness might be *the* most important thing for your typical recreational athlete! * However... When I run regression analyses on changes in VO2max, for an athlete of my current fitness ~50ml/kg/min, this low intensity work is generally not sufficient to lead to changes. The next zone up - Zone 1 (~65% MHR) does lead to positive changes. * However... In higher fitness athletes (~70ml/kg/min), Z0 is generally sufficient to lead to changes in VO2max. A number of Pro's that I've worked with have done a lot of their volume at <60% Max HR & have shown fitness (VO2max) improvements with higher training loads below this point. Mind you, even when they are below 60%MHR, their total power output and total O2 uptake is higher than mine in my 65-75% range. @StephenSeiler has spoken before about this as there being sufficient "oxidative flux" with elites even at low heart rates to lead to positive fitness adaptations. So, in summary, in my experience... * Easy movement (Z0) is good for all, but the reason that it's good likely changes with fitness - more metabolic benefit for low-moderate fitness & cardiovascular benefit for high fitness.