Impact of anaerobic training on aerobic adaptations

[Damon Stewart]

Does anybody here know the impact of finishing an aerobic (sub 70%) training session with anaerobic training? Specifically, if I do a 30-60 minute row/run piece will doing sprints or high intensity interval training afterwards mute the training effects I'm looking for: increased capillary density, left ventricle enlargement, etc.

[Geoff Archibald]

I would do the intervals first and then follow up with a long slow run.

[Steven Low]

If you're looking for the aerobic adaptations you listed you should be just running at around anaerobic threshold.., maybe slightly above... for the 60 minutes.

Don't need to finish off with anaerobic sprints at all.

That said, if you were looking to get in race shape finishing off with anaerobic sprints or having some HIIT days would be good. But otherwise, if you're looking for the aerobic adaptations you should be doing lots of volume of around anaerobic threshold running.

[CJ Kim]

Originally Posted by Steven Low

If you're looking for the aerobic adaptations you listed you should be just running at around anaerobic threshold.., maybe slightly above... for the 60 minutes.

Don't need to finish off with anaerobic sprints at all.

That said, if you were looking to get in race shape finishing off with anaerobic sprints or having some HIIT days would be good. But otherwise, if you're looking for the aerobic adaptations you should be doing lots of volume of around anaerobic threshold running.

Actually, there is a good journal article on this very topic.

http://journal.crossfit.com/2003/06/...ing-jun-03.tpl (safe)

It says just the opposite, that anaerobic training can match endurance training for aerobic benefit. And anaerobic training has additional first wave adaptations and increased functional strength.

[Steven Low]

Originally Posted by CJ Kim

Actually, there is a good journal article on this very topic.

http://journal.crossfit.com/2003/06/...ing-jun-03.tpl (safe)

It says just the opposite, that anaerobic training can match endurance training for aerobic benefit. And anaerobic training has additional first wave adaptations and increased functional strength.

Physiologically, that is wrong.

What you are terming "anaerobic" training is actually mixed modal conditioning.

Anaerobic is pretty much exhaustive glycolytic which is consumed approximately within 30s maximum (e.g. the wall in 400m).

Anaerobic confers no actual cross benefits to aerobic training even though the pathways occur simultaneously.

400m for example is about 60/40 anaerobic/aerobic and 50/50 in women.

Training purely anaerobically for this even does not actually give you world class results (well, maybe unless you're usain bolt...). You need aerobic work to make this happen hence Clyde Hart's stuff on the subject of repeat interval 200s.


Don't worry though.. it's not just you. Most people have an incorrect view of the energy pathways.

Anaerobic training itself (adaptations such as glycolytic enzymes,etc) confers zero pathway benefits to aerobic training (increase aerobic enzymes, mitochondria proliferation, capillary density, etc). It's just that they are trained nearly simultaneously so there is some adaptation in each.

If you want to bias towards an adaptation you have to train towards the adaptations -- not do mixed modal conditioning and hope to try to get benefits for each which will not actually give the benefits you're looking for.


Put it this way.... let's use an analogy that's way easier to understand.

CF trains both strength and endurance. But if you want strength OR endurance you're going to have to focus moreso on those aspects and qualities and NOT train too much metcon work. You have to lift heavy weights (strength) or run a lot for a long time around anaerobic threshold (endurance).

You can't produce "elite" strength by doing CF nor "elite" endurance. You'll just get an "elite" generalist. The same is true of trying to get benefits from the energy pathways. You can't get both optimally at the same time, and they don't confer benefits to each other (after all they are separate physiological adaptations focusing on improving different aspects e.g. strength vs endurance).

[Casey Raiford]

Your posts are solid gold; thanks much for your time, Steven.

[John Swanson]

Originally Posted by Casey Raiford

Your posts are solid gold; thanks much for your time, Steven.

I feel the same always very helpful

[Donald Lee]

If I am recalling correctly, left ventricular volume hypertrophy is best achieved at about 65-75% of maximal HR because stroke volume tops off.

Doing hours and hours of steady state work that endurance athletes tend to do works the most oxidative muscle fibers.

As a mixed modal athlete, you don't need to focus on that as much; hence, you don't need to do miles and miles and miles on end.

So, while a long distance runner might use slow, steady running for both general and specific adaptations, a mixed modal athlete does not.

This is also because increase in capillary density is localized. Capillaries aren't in your heart, they're in your skeletal muscle.

Maybe I'll write more later, but I'm short on time.

[Steven Low]

Originally Posted by Donald Lee

If I am recalling correctly, left ventricular volume hypertrophy is best achieved at about 65-75% of maximal HR because stroke volume tops off.

Doing hours and hours of steady state work that endurance athletes tend to do works the most oxidative muscle fibers.

As a mixed modal athlete, you don't need to focus on that as much; hence, you don't need to do miles and miles and miles on end.

So, while a long distance runner might use slow, steady running for both general and specific adaptations, a mixed modal athlete does not.

This is also because increase in capillary density is localized. Capillaries aren't in your heart, they're in your skeletal muscle.

Maybe I'll write more later, but I'm short on time.

This is correct.

Anaerobic threshold around untrained humans is about 60% vo2max (which is similar to max HR).. if you train slightly above that you'll get in the area where you get that maximal left ventricular hypertrophy

And yeah on the capillary density.

Basically, if you wanna get the aerobic adaptations maximally you train aerobically. You wouln't add in the sprints in the end.

However... there are reasons/cases for adding in sprints dependingon other adaptations you may want.

For example, kenyan/ethiopian runners add in sprints near the end of their workouts for marathon/half-mara/10k/5k training because it simulates sprinting to the finish line which is obviously useful.

[Damon Stewart]

Got it, thank you. After 7 years of anaerobic training am experimenting with increasing my aerobic capacity. Any thoughts on Lydiards's assertion that max anaerobic capacity is a derivative of aerobic base?