When we hear the word "endurance" most of us go straight to thoughts of LONG bouts of aerobic feats of exercise- like marathons or triathlons. This is the first, in a series of blog posts, aimed to shift your thinking about endurance to a new nuanced way of understanding this term. When exploring endurance in reference to exercise it can mean muscular endurance, aerobic endurance or anaerobic endurance and increasing your capacity in any of these areas will require drastically different training protocols. However, the beauty of endurance training is that you can increase "overall endurance" quite easily by focusing on any of these subsets or you can lump them all together. I'm going to take the 10,000 foot view of this to simplify it as much as possible and make the information I share with you understandable and accessible. There are many methods of increasing endurance and some are more effective than others. Let's start by dissecting HIIT (high intensity interval training) and its role in endurance training. HIIT is all the rage and has been for quite some time. Popular "HIIT" classes at gyms are stuffed with sweaty people getting their butts kicked for 45 min to an hour and feeling really proud of themselves albeit somewhat beat up. I'm about to bust your bubble if you are one of these class members- you aren't actually doing HIIT. Is the workout hard? Hell yes, but you can't maintain HIIT levels of intensity for 45 min. If it is truly a HIIT exercise class, then the sessions are meant to be 4 min to maybe 8 min long and you may puke. I don't see a lot of hands raised to sign up for that class. *Full disclosure: I used to teach a HIIT class, I loved teaching it and I loved kicking everyone's butts, but I'm older (and perhaps a bit wiser) and now I see the error of my ways. No matter how many times Myles tried to convince me that kicking others and my own butt over and over again was really not beneficial I just didn't want to hear it. Now I have seen the light so I'm hoping to enlighten all of you too. Doing HIIT style bouts of exercise are super beneficial for increasing your endurance- even though that seems counter-intuitive given the short duration of the session. The important caveat when doing HIIT workouts is to really get yourself to 90-100% (of either heart rate or effort level- depending on the length of the interval) every interval until you have reached your end set/rep or your heart rate/intensity just can't get there anymore. Many of us spend a majority of our time in a 75%-90% intensity range and think we are killing it because we are sweaty, feel exhausted and even beat up and sore after our workouts and we burn a bajillion calories. I'm here to tell you, this is not the way to better health, but rather a way to spin your wheels and possibly end up injured or burnt out. You may be wondering, how could it be good for me to work at 90% and nearly puke and not good for me to work at 80%? The answer is that we spend WAY too much time working at 80% and our energy would be better spent in lower and/or higher intensity exercise. There are many studies conducted on both athletes and regular exercisers that back up this statement. Even professional level MMA fighters only do 1-2 HIIT workouts a week. If you can get one bout of HIIT work done every week, you would see major gains in your overall anaerobic capacity. An example of this would be, riding an assault/airdyne bike all out for 20 secs, recover for 40-60 seconds and do it again until you reach 8 sets or you can't get your RPM's up there anymore. DONE! Does it suck- well yeah, but it's super short and the benefits are huge so you can do something sucky for a little while, right? You will feel better after doing that then you would after leaving a HIIT class breathless and sore but not having created enough of a stress response in your body to drive a physiological change. The hardest part of true HIIT is getting your intensity to where it needs to be. To start, knowing what your max heart rate is would be an extremely useful benchmark to base your training off of. To find this you would have to do a max heart rate test and we can help you with this if you are interested. The classic formula of 220 minus your age = your max heart rate is a rough approximation, but not nearly as effective as actually knowing what your max heart rate is in real time. The easiest route to get to high intensity is to use a piece of cardio equipment (airdyne, rower, ski erg, versa climber) that can measure distance or cadence or speed (or all of the above). The other option is to do strength/bodyweight related work- like kettlebell swings, sprints uphill, squat jumps or sled push/pulls. The difficulty when using those sorts of exercises is that you are more likely to get injured at that rate of intensity whereas using the cardio equipment you will be pretty safe during intense repeat bouts. The pros of HIIT are pretty straight forward. Creating maximum stress with a very small time investment yields major results for your time/effort. The types of results range from cardiovascular health increasing (mainly due to VO2max improving), insulin sensitivity improving, and promoting the growth of mitochondria within cells. The cons are if you are deconditioned this is not a good way to start and you can hit plateaus faster and possibly suffer from overtraining.
My next post will focus on LISS (low intensity steady-state) training and how that can be used as a building block for your overall cardiovascular fitness. Before you attempt any type of HIIT workouts, you need to make sure you have a solid cardiovascular base in place to be able to maximize your results from HIIT and avoid injury or overtraining issues.