Exercise Delays Onset Of Chronic Illness

There are a huge amount of studies ratifying the fact that exercise delays, and in some cases even avert the onset of disease. There will always be divergent opinions on what specific type of exercise to pursue. Perhaps the more important debate, however, should be around how much exercise is optimal, and at what intensity.

HIIT Is Highly Effective Form Of Exercise

High intensity interval training (HIIT) nowadays has a significant number of studies behind it demonstrating that it can efficient alternative to the traditional endurance based training. It has been shown to have similar and indeed often superior benefits to traditional endurance training in both healthy and unhealthy people.

As discussed elsewhere, there is a growing body of research demonstrating that short-duration high intensity interval training can lead to similar positive changes to moderate intensity endurance training, with a fraction of the actual exercise time or total time commitment. Traditional endurance based moderate-intensity long-duration exercise has also been shown to have some shortcomings when it comes to cardiac patients. In fact, it can even be a factor in inducing heart attacks.

However, all-out intensity training like the Wingate model is also likely to be unsafe for cardiac patients.

The Wingate model has subjects performing 30 second bursts of all-out exercise against (170% of former VO2 max and 100% of peak power), followed by 4 minutes of rest. This is repeated 4-6 times. Several modified versions of short-duration HIIT have been designed, and we will take a quick look at two of the most recent ones.

Two HIIT Training Regimes That Have Been Modified For Cardiac Patients

1. The Gibala Short-Duration High-Intensity Interval Training Protocol

This HIIT training regime was designed as an alternative to the all-out programs in order for it to be safely available to people with certain diseased conditions such as cardiac problems, Diabetes type 2 and obesity.

They extended the model to people with these types of chronic metabolic diseases by reducing the intensity and increasing the duration, but nevertheless maintaining the time efficiency. Here is a quick breakdown of their program:

• 60 seconds of 90% maximal heart rate exercise (which is apparently 60% of peak power)
• 60 seconds of recovery (low intensity cycling – just turning the pedals over)
• This is repeated 10 times for 10 minutes of training and 20 minutes of total exercise time.

This model was found to have similar efficacy to the standard short-duration HIIT model!

2. The Gayda Model For Short-Duration HIIT

The Cardiovascular Prevention and Rehabilitation Centre in Montreal (ÉPIC) has researched its own model for short-duration HIIT.

They agree with Gibala et al that the Wingate model is not safe enough for chronic metabolic disorders. However, they feel that the Gibala model (80-90% maximal heart rate, 60% peak power) does not have the intensity to constitute HIIT. They are also unsure whether the safety of this model has yet been demonstrated, and feel it requires longer term testing.

The awesome thing about the Gayda model is that it has undergone long-term testing!

Their model involves 15 or 30 second bursts of 100% peak power (170% of former VO2 max), interspersed with passive recovery periods of exactly the same duration.

Relative to longer exercise bouts with less intensity (such as the Gibala model), they found that these short bursts resulted in the following:

• longer total exercise time (the high intensity time),
• similar amounts of time spent at VO2 max,
• a lower rating of perceived exertion, and
• higher likelihood of completing the prescribed exercise sessions.

In comparison with traditional endurance exercise this protocol was found to be not only more efficient, but also safer. Unlike endurance exercise it was found to ‘not induce significant arrhythmias or myocardial cardiac injury in stable coronary and heart failure patients’.

6 Ways The Gayda Model Of Short Duration HIIT Proved To Be Superior To Endurance Training.

Over a 9 month period with obese subjects it was found to be superior to moderate intensity long duration exercise in the following areas:

1. maximal exercise capacity
2. muscular endurance
3. abdominal obesity
4. improved body composition
5. cardio-metabolic profile
6. cardiovascular risk
7. metabolic syndrome prevalence

They concluded that 2 weekly sessions of their modified short-duration high intensity interval training program was safe for use with obese individuals.

Specific Cardiac Populations

There are similar programs that have been tailor made and validated for various other specific cardiac populations.

References

1. Burgomaster KA, Howarth KR, Phillips SM, Rakobowchuk M, Macdonald MJ, McGee SL & Gibala MJ (2008). Similar metabolic adaptations during exercise after low volume sprint interval and traditional endurance training in humans. J Physiol 586, 151–160.
2. Burgomaster KA, Hughes SC, Heigenhauser GJ, Bradwell SN & Gibala MJ (2005). Six sessions of sprint interval training increases muscle oxidative potential and cycle endurance capacity in humans. J Appl Physiol 98, 1985–1990.
3. Gayda, M., Juneau, M. and Nigam, A. (2012), Comment on the paper by Gibala, Little, Macdonald and Hawley entitled Physiological adaptations to low-volume, high-intensity interval training in health and disease. The Journal of Physiology, 590: 3389. doi: 10.1113/jphysiol.2012.232652
4. Gibala MJ, Little JP, Macdonald MJ, Hawley JA. (2012). Physiological adaptations to low-volume, high intensity interval training in health and disease. J Physiol. 590:1077–1084.
5. Guiraud T, Juneau M, Nigam A, Gayda M, Meyer P, Mekary S, et al. Optimization of high intensity interval exercise in coronary heart disease. Eur J Appl Physiol. 2010;108:733–740.
6. Hwang CL,Wu YT & Chou CH (2011). Effect of aerobic interval training on exercise capacity and metabolic risk factors in people with cardiometabolic disorders: a meta-analysis. J Cardiopulm Rehabil Prev. 31, 378–385.
7. Meyer P, Normandin E, Gayda M, Billon G, Guiraud T, Bosquet L, et al. High-intensity interval exercise in chronic heart failure: protocol optimization. J Card Fail. 2012;18:126–133.
8. Rakobowchuk M, Tanguay S, Burgomaster KA, Howarth KR, Gibala MJ & MacDonald MJ (2008). Sprint interval and traditional endurance training induce similar improvements in peripheral arterial stiffness and flow-mediated dilation in healthy humans. Am J Physiol Regul Integr Comp Physiol. 295,236–242.
9. Tjønna AE, Stølen TO, Bye A, VoldenM, Slørdahl SA, Odeg°ard R, Skogvoll E &Wisløff U (2009). Aerobic interval training reduces cardiovascular risk factors more than a multi-treatment approach in overweight adolescents. Clin Sci. (Lond) 116, 317–326.
10. Wisløff U, Støylen A, Loennechen JP, Bruvold M, Rognmo Ø, HaramPM, Tjønna AE, Helgerud J, Slørdahl SA, Lee SJ, VidemV, Bye A, Smith GL,Najjar SM, EllingsenØ & Skjaerpe T (2007). Superior cardiovascular effect of aerobic interval training versus moderate continuous training in heart failure patients: a randomized study. Circulation 115, 3086–3094.