Blatherwick: HIIT for endurance

07/21/2020, 2:45pm CDT By Jack Blatherwick

Postpone the ‘aerobic-cardio’ workout until you retire from hockey

The word ‘Cardio’ has been added to a long list of words that have distracted hockey players and coaches from training young athletes intelligently (the word ‘young’ for this purpose means under 20 or so). Misleading words like ‘aerobic training’ are used to describe slow endurance conditioning, a commitment of time and effort that should be invested more wisely while you’re still young. ‘Anaerobic training,’ is also used incorrectly to describe high-intensity training. Those two words are not only a distraction, but are only accurate if, during the training you don’t breathe.

With that opening paragraph I might raise questions from faithful ‘Cardio’ proponents, but will more likely decrease my chances when I apply for a job. No problem. I’m not looking for a job.

I promise I won’t get into the depths of biochemistry and physiology to explain the opening paragraph – a project that would require volumes to write (thousands of pages). Instead, I’ll start from the point where a logical approach to HOCKEY ENDURANCE should start – but never has. Let’s ask “What does endurance mean in a hockey game?  What would a player like to maintain at the highest possible level for each shift, and then for an entire game?

HOCKEY ENDURANCE is the maintenance of skating speed, quickness, agility (changing directions efficiently), explosive strength, and of course, stick skills, decision-making, and grit or mental toughness.

If you didn’t see the word ‘slowness’ in that list, it’s because we aren’t defining endurance from a basic exercise physiology textbook, where we were told (not by hockey people but by scientists who hadn’t played a lot of hockey) that we have to establish an aerobic base before ‘conditioning’ our players.

Yes, we need an aerobic base, and we need cardiovascular fitness. But young athletes want training to help them play at a higher level (this might mean college or pro hockey, but more immediately it might mean winning a championship this year, or just playing better than last season – a higher level of play).

If that’s the goal, it is essential to execute present and future skills at a faster pace. And the law of neuro-science that absolutely MUST guide our training is this: whatever you repeat often is hard-wired into your Central Nervous System (CNS). This means you become what you repeat often. Do NOT repeat slowness, even if you call the repetitions ‘endurance conditioning.’

Slowness training – ‘aerobic conditioning’ – has to be left until you give up the chase.

High Intensity Interval Training (HIIT) is the answer when you’re still young enough to improve. If programmed wisely, it will increase speed and all other qualities on the HOCKEY ENDURANCE list – and (take note !!!!!) we also increase cardiovascular fitness, respiratory function, vascular density (more blood vessels – capillaries – to deliver oxygen and other nutrients to muscles), more mitochondrial enzymes for efficient (aerobic) metabolism of oxygen and other nutrients.

HIIT also prepares the body for recovery, which is more important in hockey than in any other sport. Why do I say this? We have more opportunities for recovery in hockey: (1) during a shift when coasting is your smartest decision, because you’re headed in the right direction at the right speed; (2) between shifts while you sit; (3) Intermissions (we have two, most sports have just one).

Coasting (or decelerating) in hockey happens many times a shift, even in the most intense games.

In our sport (unlike soccer or basketball where jogging takes a lot of energy) these moments during a hockey shift are a convenient time for our bodies to burn lactate aerobically, the most efficient way to produce ATP for further muscle movement.

Dr. George A. Brooks was not believed by many other physiologists in the 1970s when he contended that lactic acid (or lactate) was not a metabolic poison – not the cause of muscular fatigue as people before him believed. Today, he’s a hero in this field of respiratory physiologists – and would be a hero in hockey if we’d learn from his research.  If you Google him, you’ll find that he is cited by thousands of knowledgeable scientists.

Through a half-century of research, he has shown (and now, hundreds of others have as well) that indeed, lactate is the most abundant source of energy from the breakdown of carbohydrate.  He refers to the lactate shuttle – the way lactate results from the anaerobic breakdown of glucose (or muscle glycogen), and is then broken down further to produce ATP (energy) aerobically, either in the same muscle, or in other muscles or organs of the body.

The recovery intervals during HIIT training increase the mitochondrial (aerobic) enzymes in fast-twitch (FT or Type-2) muscle fibers, so they gain increased endurance capacity along with the speed, strength, and explosiveness we are ultimately training for.

Only HIIT training, and only FT muscle fibers can increase explosiveness, and thanks to Dr. Brooks, we know that HIIT training also increases aerobic-cardiovascuar-metabolic endurance.  We found this to be true in a pre-season study at Hamline University in 1981.  Three times per week for six weeks we did HIIT training off-ice for 60-90 minutes. There was no distance training or what folks would call ‘Cardio.’

All markers of speed and explosiveness (on the ice and off) improved significantly. In the lab, we found that important markers of endurance also improved – actually, to a greater extent than what is commonly shown after six weeks of aerobic conditioning.

In the next column a graph from that lab testing will show clearly that after six weeks of HIIT training, players have much greater cardiovascular and energy-use efficiency, plus greater total work capacity, which is a function of both aerobic and anaerobic metabolism.