Stadium Sprints, Energy Systems and Conditioning

5 Rounds

5 Stadium sprints

~20 yards up.

(25 total sprints)

Supersetted w/

44lb kb x 20 swings

(80 total swings)

I switched it up a bit with a new style of stadium runs.  Normally we do these at a brisk jog up and down the stairs, jog to the kettlebell, immediately start swing, then jog back and start up another round.  Instead of doing continuous rounds with no breaks, I opted to sprint each run up the stadium at near max effort.  Then I would walk down the stairs, walk to the next set of stairs, and restart  a sprint.  After 5 sprints and the kettlebell swings, I rested for 90-120 seconds allowing my heartrate to drop.  I noticed two things tonight when doing the sprints as compared to the more sustained runs.  First, my legs didn't burn as much.  Second, I was surprised at the speed I maintained for 25 short sprints.

Each 20 yard sprint up the stairs took around 4-5 seconds, putting it squarely in the alactic anaerobic/ATP Creatine energy system realm.  But, I've often wondered why "alactic anaerobic" conditioning work still leaves me gasping for air. (Sprints, prowler runs).  If its anaerobic, why the fuck am I breathing so hard?  If its alactic, why the fuck are my legs burning?  Well, I came across a nifty chart tonight showing the mix of energy systems used during different track and field events.  Even a short sprint isn't really "anaerobic," its just mostly anaerobic (click to enlarge):

Recovery

According to this site it takes 1.5-3 minutes for the ATP/Phosphate system to recover fully after being depleted in 10 seconds.  This makes sense.  1.5-3 minutes is the standard rest time for shit like squats and true speed work.  (as an aside, I now realize I'm mostly being a pussy if I feel I need to rest more than 3 minutes during normal everyday sets... yes, there is some lactic acid buildup occurring, but not a ton. Also, max work or near limit sets across is different).

The same site notes that it takes up to an hour for the lactic aerobic energy system to fully recovery.  The lactic anaerobic energy system (as opposed to alactic) is also glycolytic - ie, it uses glucose for fuel instead of ATP/Phosphate.  Knowing this, I now understand why going heavy/maxing in the 1-3 rep range when carb depleted is totally fine for me, but 5x5 sets become very difficult and exhausting.  The former uses little glycogen for fuel, the latter becomes heavily glyocgen dependent after 10 seconds.

Training ATP/Creatine Phosphate through Alactic Anaerobic Work

Why does any of this matter?  I now know how to intelligently incorporate "conditioning" into training based on specific objectives.  People often recommend sprints/hill runs for fat loss.  You will also see guys like Jim Wendler saying run hills to condition claiming it makes your legs strong.  I've run hills for two years now and never felt they made my legs any stronger.  Really, I always just felt like all the squatting/deadllifting made me pretty good at running hills.  Now I understand where Jim is coming from.  I don't think that running hills makes you "stronger" as in builds huge legs (though it probably induces hypertrophy in newer trainees), it just develops the ATP/Creatine Phosphate system, enhancing the energy system used during squats.  For me, this energy system is already pretty well developed.  Obfuscation of the term "conditioning" has led guys like Anthony Mychal to write articles reminding people that training  the aerobic energy system is still important for sports.

Training the Glycolytic System through lactic Anaerobic work

People that recommend sprints (alactic anaerobic work) for fat loss are wrong, at least if they mean true sprints where you recover completely in between sets.  True sustained interval work (lactic anaerobic) has to be much better for fat loss.  It is more likely to deplete glycogen because it initially relies on the glycolytic energy system for fuel.  Once glycogen is depleted, fat has to be burned.  Further, as the chart above shows, lactic anaerobic work uses a higher percentage of the aerobic system.  Depending on heartrate, the aerobic system system uses high percentages of fat for fuel.  The muscle mag guys recommend interval type training because it taxes the aerobic system (hence burns fat), but is limited in duration by lactic buildup, thus minimizing muscle loss that can occur during sustained aerobic activity.  Going back to hill sprints.  They can be good for fat loss, but you need longer hills and shorter rest periods.

Non-Exercise Physical Activity

One of the best takeaways from the V-Diet was the non-exercise physical activity walks ("NEPA walks.").  Slow walking is glycogen sparing.   Further, walking slow keeps the heartrate low enough to remain out of the aerobic exercise zone, greatly minimizing the chance of losing muscle.  Thus, slow walking burns calories through increased activity, but doesn't waste glycogen stores and doesn't waste muscle.  The downside to NEPA walks is it takes a shitload of slow walking to burn an appreciable amount of calories.  But in general, non-exercise physical activity (taking the stairs) is a good mindset when weightloss is the goal.

The takeaway from all of this is that very deliberate conditioning styles should be used and implemented based on training objectives.  Just like weightlifting, where certain rep ranges emphasize either hypertrophy or strength (but even 1 rep builds some muscle, and 20 reps builds some strength), forms of conditioning emphasize different energy systems.  Energy systems can be trained to maximize high intensity performance, or to emphasize body recomposition.  To some degree, any form of conditioning still develops all of the energy systems.  The point is, "conditioning" doesn't need to be just running around doing random shit to make sure you are working hard.  That is crossfit.  They have no plan, no structure, and don't know what qualities they are trying to develop.  Thus, they end being completely average in everything they do.

In Sum:

• Walk slowly to burn fat and improve body composition.
• Perform sustained alactic anaerobic work (high intensity interval training) to improve aerobic capacity, burn some fat, and improve body composition while holding on to muscle.
• Run pure sprints and rest completely in between sets to develop speed and improve the ATP/Creatine Phosphate energy system for heavy lifting.
• Regular aerobics are still completely gay, unless your goal is to look like a feeble marathon runner.