Science Summary: Aerobic Exercise (Cardio or Weights Part 5)

This post is a continuation on my series through Alex Hutchinson’s Which Comes First, Cardio or Weights? All of the following questions are taken from this book and the answers are paraphrased from the authors words with my interpretations and thoughts added in.

— Scott

Why should I do cardio if I just want to build my muscles?

Short Answer: Most health benefits from exercise are tied to cardiovascular fitness.  Additionally, cardiovascular fitness is a good predictor of overall athletic performance.

Long Answer:  While there is a correlation between reduced risks of disease and weight training, the correlation is much stronger with cardiovascular fitness.  Additionally two separate studies in 2009 (one of World Cup snowboarders and one of golfers on the Canadian National Team) found cardiovascular performance was strongly correlated with tournament placing.  The more cardiovascularly fit the athlete, the higher they placed.  In order to receive the benefits of cardio, research has show the effort expended must be greater than 50% max effort.

How hard should my cardio workout feel?

Short Answer: A rule of thumb is 70% should feel easy (3-4 on a 1-10 scale), 20% should feel moderate (5-6), and 10% should feel hard (8-9).

Long Answer:  Your body works in three different cardio states.  The first is an aerobic state where you are efficiently converting oxygen to energy for movement.  The second is a transitional state where you are using just a bit more energy than your body has the oxygen efficiency for.  The final stage is anaerobic which is where your body can not process oxygen fast enough for the required energy expended.  These three zones feel distinctly different and research has show that 90% of people are able to accurately perceive which of the three zones they are in.  The study concluded most of the other 10% are egoists who refuse to admit when they are being challenged.  This blend of 70-20-10 may seem very heavy on low intensity work, but it is important to remember that the lowest category equates to 50-80% of maximal heart rate which adds up over long periods of time.

How do I determine my maximum heart rate?

Short Answer:  The best way to determine max heart rate is to spend 15-20 minutes performing progressively harder cardio exercise and concluding with a full sprint while observing your heart rate and watching for a maximum plateau.

Long Answer:  Maximum heart rate is an easy, accurate way to determine effort.  The historic rule of thumb is 220 minus your age but this is very inaccurate.  The above method is version of a cardiac stress test which can be done on your own or in a lab for more accurate results.

What’s the best way to breathe during exercise?

Short Answer:  There is no definitive proof for a set breathing pattern being the most efficient.

Long Answer:  There are many different common breathing patterns found in competitive cardio athletes.  Historically, athletes have suggested rhythmic breathing based on stride cadence is the most efficient way to breathe.  A 2009 study by the Institute of Sport Science found that athletes who actively monitored their breathing were actually 10% less efficient than their counterparts who let their mind wander and let the breathing patterns form naturally.  This research is related to breathing during aerobic exercise however, controlled breathing for weight training has been demonstrated to improve performance.

Will running on hard surfaces increase my risk of injuries?

Short Answer:  No

Long Answer: Research from a 2002 study demonstrated hard surfaces do not result in greater impact than soft surfaces because the body adapts to compensate and absorb the impact more.  Another study done by Brazilian researchers in 2010 found a 12% increase in impact on hard surfaces as opposed to soft ones.  Ultimately, research concludes hard surfaces are no more likely to cause injury from impact than soft surfaces are.  Injuries from modified stride between surfaces are another story though.  While no research has proven a connection between technical changes in stride between surface causes increased injury rates, it hasn’t been ruled out yet either.  It is more likely that surface instability and uneven surfaces increase risk than surface toughness.

Do I run “wrong?”

Short Answer: Maybe?

Long Answer:  Research has shown that new stride patterns can be taught, but whether the new form is better is under debate.  Research suggests that experienced runners naturally adapt to the most effective technique.  By changing their natural technique, researchers found increased rates of injury and decreased cardiovascular efficiency in the majority of athletes.  Novice runners may benefit from running instruction but they will more likely benefit more from finding their own form.  A separate study conducted by the University of Wisconsin in 2010 found that efficiency could be improved and injury rates lowered in novice runners by increasing stride rates by 5-10%.  This shortened stride length while allowing the individual to maintain their learned technique.

What’s the best way to run up and down hills?

Short Answer:  Slower uphill and as fast as is safe downhill

Long Answer:  A 2010 study conducted by Australian researchers looked at runners on a 6 mile course with several hills.  They found that runners tend to push harder uphill in order to avoid losing speed but after this extra effort they took on average 78 seconds to regain their level ground speed after returning to flat ground.  This suggests that the time saved by increasing effort uphill is less than that saved by lowering speed and returning to normal pace more quickly.  On downhill portions, researchers found runners didn’t work at their most efficient level as they limited speed to avoid injury.  Theoretically the runners were able to push harder, but terrain may have been a limiting factor.

Does pumping my arms make me run faster?

Short Answer: Maybe to some extent, but not in the way you would think.

Long Answer:  There has long been a debate over whether arm motion while running simply acts as a counter balance for motion or if increased muscle usage in the arms adds power and efficiency to stride.  Researchers in Yugoslavia added weights to participants arms while sprinting and found no reduction in efficiency which supported the counterbalance theory.  A 2006 study by researchers at the University of Michigan found there may be a neurological effect of pumping your arms though.  This research suggests that the neural components of arm and leg motion come from similar areas of the brain and increase efficiency when combined.

Do spinning classes offer any benefits that I can’t get from biking on my own?

Short Answer:  Yes, but they are mostly mental.

Long Answer:  While spin classes are largely individual, researchers have found that group exercise has interesting benefits.  Researcher Carl Foster found that spin class members were able to exceed their calculated VO2 Max while in class.  What this means is the class was able to encourage the participant to push harder than doctors could or they were able to individually.  This may be risky in populations prone to heat trouble, but is beneficial for those who struggle to motivate themselves to work.

Will taking the stairs make a real difference in my health?

Short Answer:  Yes

Long Answer:  As with most exercise, some is better than none and more is always better.  Researchers found that by adding about 10 minutes of stairs spread across an entire day improved aerobic fitness in individuals by 17% over an eight week program.


Science Summary: Full Body vs Split Routines

In the body building world, split routines have become to go to for maximizing the amount of training allowed in a week.  A split routine consists of targeting specific muscle groups every day rather than working all major lifts at one time.  A common example is Day 1 – Legs, Day 2 – Chest + back, Day 3 – Shoulders + Biceps + Triceps, Day 4 – Rest, performing multiple exercises for each group on the specified day.  This cycle allows for 6 days of work per week rather than the traditional 3 days associated with full body sets.  This month, a group of researchers out of Lehman published an analysis of the effects of split training versus those of full body training to The Journal of Strength and Conditioning Research.  The full article can be found here.

In this study, 20 participants were randomly assigned to one of two groups.  The first group was assigned to a full body workout routine in which they exercised three times per week working each muscle group once per session.  The second group was assigned to a split routine in which the worked out three times per week but only worked 2-3 muscle groups per session but worked those groups multiple times.  Progress for both groups was assessed by one repetition maximums and muscle size.  After 8 weeks, researcher found no correlation between training style and one rep maxes or forearm hypertrophy (muscle growth).  They did find increased muscle size in the biceps and triceps of the split group, however the relative growth was so small (1.1mm, 1.3mm respectively) the application is questionable.

What this study reveals is that ultimately total volume is more important than the specific splits or routines.  That being said, split routines typically do allow for more weekly volume than full body routines.  On a split routine you can hit the same muscle groups six times per week in with standard one hour workouts.  For a full body routine, you are limited by recovery days and would most likely need two hour sessions to reach the same amount of volume.  But if the total volume is held constant, this study tells us that there is not magic benefit to either a split or a full body routine.  Routine should be determined by what allows the most volume in your schedule on a consistent basis.