Fast Talk Episode 227: How to Make VO2 Max and Threshold Workouts Work for You with Hunter Allen

Thank you for this podcast. It was helpful to hear how these different intervals should be performed and with what rest.

Having done the 4*8s (2-3min rest) last year and seeing huge improvements in my Vo2max, it was helpful to hear that how I did them (~112% ftp) was more like the high end of a Vo2max interval and less like a threshold.

If my goal is to improve Vo2max without increasing VLAmax, shouldn’t I consider putting the least strain on my anerobic system and in turn consider increasing cadence during these intervals to in turn increase arterial flow? I’ve found the cadence I do an interval greatly determines the impact on my body. For example, 95% threshold at 60rpm and my legs are thrashed, while 85rpm everything feels strong and at 105rpm my lungs/HR are on fire but my legs feel great!

Is there science to back up cadence used during the interval affecting physiological outcome?

Of note, the other thing I heard was that short VO2MAX intervals are useful for sharpening form for racing… But what if the only racing I do is against myself and the clock? Sure, some surges over hills are good, but it’s not like I have to cover an attack in a 56mi 500’ Time Trial. Is there much of a point to these kind (short VO2MAX) of intervals? Especially with a VLAMax of 0.6?

Power = cadence * torque
So, if you ramp up the cadence it requires less strength → less sore in the legs.

If you don’t race you don’t need to ice up the cake.

1 Like

No offense, but everyone needs cake!

But for srs. Just because I don’t race, doesn’t need I don’t need to top off before an event. I think the key as I was pointing out was how I top off.

Going back to the episode, there was talk about intensity but not much on cadence. Given that cadence clearly targets different systems, I was curious how that ties into the bigger picture with one’s goals and event type.

Agree, it was a really good podcast explaining the difference between threshold and Vo2 - threshold is where I need to improve for sure, and it was great to execute the 3 x 10’s today, probably the best execution I’ve done in 12 months of 4 x 8, which are also great. The extra 2 minutes made a big difference. I don’t race, so Vo2 is not a priority, but I probably do a Vo2 maybe once every 2-3 weeks just to keep that system in check. I just want a solid aerobic foundation.

Vo2 max has two components- power and VO2 and what I coach as time at intensity VO2 or HR activity. Tho there is an association between the two, meaning if you spend long enough at VO2 power you will illiciate VO2HR (in theory and all things equal), but if you spend long enough time in AT or FTP you will eventually get to 90% of max HR which is time at VO2 HR. It really depends on what you are after. I coach VO2 from HR first and I do not necessarly care if power drops as long as HR stays at 90+% of max HR, this is what gets you into trouble and when you need to “pull the plug” on an effort, the power usually is not the problem, the HR is.

As far as Vlamax goes as long as you stay away from those efforts that are 120+% of FTP you will not be training VlaMax, definelty avoid the really hard 150+% short 15-30 sec type efforts. VlaMax is associated with anaerobic power and has nothing to do with HR where as VO2 HR has the anaerobic cardio respitory piece to it, anaerobic power is defined as 120+% of FTP. If you stay true to the 112% you stated in your intervals you will not be triggering VlaMax.
Finally the cadence piece. Low cadence will cost you more metabolically, menaing how your legs feel, the fatigue per say, using a higher cadence and using velocity to derive your power will cost less metabolically. Since HR reacts to what our feet are doing, often is the case when doing VO2 work I want my ahtletes at 95-110RPM so HR gets into the 90+% MHR zone, this happens faster vs lower cadence and makes the interval time more productive. For example a 4min VO2 interval done at 107-115% FTP at 80RPM will most likely not illicit the HR high enough and if it does rise it will not be until end of the interval, that same interval done at 95-100RPM accelerates HR and you may get a full 3min out of the 4 at 90+%MHR which is what you want when doing VO2 work.
I hope this helps and happy training.