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Why Does Aerobic Fitness Take So Long?

“WHY IS IT TAKING SO LONG” ? Why does running still feel so hard? Why is my heart rate still spiking when I swear I’m running easy? Why am I not getting faster?

WHY ???

^ Raise your hand if you’ve ever asked these or felt these 🙋🏼‍♀️. I know I have!

When it comes to resistance training we understand that muscle takes a lot of time and work and is a slow process. Building new tissue just takes time right? We accept this even if we wish it was faster.

But the same goes for running or cardio or aerobic adaptations. We often think of these as only our lungs + heart adapting. But aerobic adaptations are ALSO MUSCLE ADAPTATIONS.

These adaptations just take … time. Months. Years. A lot of training consistently and stacking bricks.

Our body is creating new capillaries to deliver more oxygen to our muscles to be used for energy production. But we also need to develop the aerobic enzymes and mitochondrial adaptations to allow us to use that oxygen. For most of you your limit is not breathing enough — it’s your muscular ability to USE that oxygen for energy metabolism.

The better our muscles are at doing this the better our mile times get, the easier our zone 2 efforts become & the faster our metcons start moving.

This isn’t to say your heart and lungs aren’t also adapting too. But it’s not the rate limiting step for most of you (or me too!). And sometimes the answer to this is to just keep training. Give it time. Wait for that “breakthrough” workout when you realize your body adapting and things are getting easier.

Of course if you’re not following something structured this will be harder. But if you have a program or plan or coach — give your body time. Physiology takes time. We do not adapt over night! We have to keep giving our body the stimulus so it adapts to it. This is why we want to increase frequency or volume or intensity with time as well.

If you need a running plan then we’ve got you with the TLM run programs. Or our conditioning programmed into every lifting plan. With our run plans you can string together multiple programs to work toward these goals over months or a year or more.

But remember this next time you’re feeling frustrated.💪🏻

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Hey, I'm Lyss!

I’m Exercise Physiologist, sports nutritionist, weight lifter, and ultra runner. I am here to bring science to your training in a no-nonsense way. I have helped thousands of women crush big lifting goals, cross race finish lines, and even do both. I’m here to help you do the same!

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