High-intensity interval training

From Wikipedia, the free encyclopedia

  (Redirected from High-density exercise)
Jump to: navigation, search

High-intensity interval training (HIIT) or sprint interval training is an exercise strategy that is intended to improve performance with short training sessions. HIIT is a form of cardio which is beneficial to burning fat in a short and intense workout. Usual HIIT sessions may vary from 15–30 minutes. Most HIIT sessions have a 2:1 ratio in terms of time. For example, for running, a HIIT session may be something as 60 seconds jog, 30 seconds sprint.

Contents

[edit] Procedure

A HIIT session consists of a warm up period of exercise, followed by six to ten repetitions of high intensity exercise, separated by medium intensity exercise, and ending with a period of cool down exercise. The high intensity exercise should be done at near maximum intensity. The medium exercise should be about half-maximum intensity. The number of repetitions and length of each depends on the exercise. The goal is to do at least six cycles, and to have the entire HIIT session last at least fifteen minutes and not more than twenty.

HIIT is an excellent way to maximize your workout if you are limited on time. Many fitness experts such as Jeff Halevy, a major proponent of HIIT, have made this methodology a cornerstone of their routines for these reasons.[1]

[edit] Tabata Method

A popular regimen based on a 1996 study[2] uses 20 seconds of ultra-intense exercise (at 170% of VO2max) followed by 10 seconds of rest, repeated continuously for 4 minutes (8 cycles). In the original study, athletes using this method trained 4 times per week, plus another day of steady-state training, and obtained gains similar to a group of athletes who did steady state (70% VO2max) training 5 times per week. The steady state group had a higher VO2max at the end (from 52 to 57 ml/kg/min), but the tabata group had started lower and gained more overall (from 48 to 55 ml/kg/min). Also, only the tabata group had gained anaerobic capacity benefits unlike the steady state group.

[edit] Benefits

Studies by Tabata[2], Tremblay[3] and others have explored the effectiveness of this method compared to traditional endurance training methods. A study by Gibala et al.[4] demonstrated 2.5 hours of sprint interval training produced similar biochemical muscle changes to 10.5 hours of endurance training and similar endurance performance benefits. According to a study by King [5] , HIIT increases the resting metabolic rate (RMR) for the following 24 hours due to excess post-exercise oxygen consumption, and may improve maximal oxygen consumption (VO2 max) more effectively than doing only traditional, long aerobic workouts.[6][7][8][9]

Long aerobic workouts have been promoted as the best method to reduce fat, as fatty acid utilization usually occurs after at least 30 minutes of training.[citation needed] HIIT is somewhat counterintuitive in this regard, but has nonetheless been shown to burn fat more effectively.[citation needed] There may be a number of factors that contribute to this, including an increase in RMR, and possibly other physiological effects.[citation needed]

High-intensity interval training has also been shown to improve athletic performance. For already well-trained athletes, improvements in performance become difficult to attain and increases in training volume can potentially yield no improvements. Previous research would suggest that, for athletes who are already trained, improvements in endurance performance can be achieved through high-intensity interval training. A recent study by Driller[10] showed an 8.2 second improvement in 2000m rowing time following 4-weeks of HIIT in well-trained rowers. This equates to a significant 2% improvement after just 7 interval training sessions. The interval training used by Driller and colleagues involved 8 x 2.5 minute work bouts at 90% of vVO2max ]], with individualised recovery intervals between each work bout.

Recently it has been shown that two weeks of HIIT can substantially improve insulin action in young healthy men.[11] HIIT may therefore represent a viable method for prevention of type-2 diabetes.

[edit] See also

[edit] References

  1. ^ Van Dusen, Allison (October 20, 2008). "Ten ways to get more from your workout". Forbes. http://www.forbes.com/2008/10/20/exercise-workout-shorter-forbeslife-cx_avd_1020health.html?. Retrieved December 14, 2008. 
  2. ^ a b Tabata I, Nishimura K, Kouzaki M, et al. (1996). "Effects of moderate-intensity endurance and high-intensity intermittent training on anaerobic capacity and VO2max". Med Sci Sports Exerc 28 (10): 1327–30. PMID 8897392. 
  3. ^ Tremblay A, Simoneau JA, Bouchard C (1994). "Impact of exercise intensity on body fatness and skeletal muscle metabolism". Metab. Clin. Exp. 43 (7): 814–8. PMID 8028502. 
  4. ^ Gibala, Martin J; Jonathan P. Little, Martin van Essen, Geoffrey P. Wilkin, Kirsten A. Burgomaster, Adeel Safdar, Sandeep Raha and Mark A. Tarnopolsky (September 15 2006). "Short-term sprint interval versus traditional endurance training: similar initial adaptations in human skeletal muscle and exercise performance". J Physiol 575 (3): 901–911. doi:10.1113/jphysiol.2006.112094. http://jp.physoc.org/cgi/content/short/575/3/901. Retrieved 2008-07-23. 
  5. ^ East Tennessee State University Thesis
  6. ^ Smith TP, Coombes JS, Geraghty DP (2003). "Optimising high-intensity treadmill training using the running speed at maximal O(2) uptake and the time for which this can be maintained". Eur. J. Appl. Physiol. 89 (3-4): 337–43. doi:10.1007/s00421-003-0806-6. PMID 12736843. 
  7. ^ Rozenek R, Funato K, Kubo J, Hoshikawa M, Matsuo A (2007). "Physiological responses to interval training sessions at velocities associated with VO2max". J Strength Cond Res 21 (1): 188–92. doi:10.1519/R-19325.1. PMID 17313282. 
  8. ^ Helgerud J, Høydal K, Wang E, et al. (2007). "Aerobic high-intensity intervals improve VO2max more than moderate training". Med Sci Sports Exerc 39 (4): 665–71. doi:10.1249/mss.0b013e3180304570. PMID 17414804. 
  9. ^ Esfarjani F, Laursen PB (2007). "Manipulating high-intensity interval training: effects on VO2max, the lactate threshold and 3000 m running performance in moderately trained males". J Sci Med Sport 10 (1): 27–35. doi:10.1016/j.jsams.2006.05.014. PMID 16876479. 
  10. ^ Driller, Matthew; Fell, James; Gregory, John; Shing, Cecilia and Williams, Andrew. (2009). The effects of high-intensity interval training in well-trained rowers. International Journal of Sports Physiology and Performance, 4(1)IJSPP
  11. ^ Babraj J, Vollaard N, Keast C, Guppy F, Cottrell G, Timmons J (2009). "Extremely short duration high intensity interval training substantially improves insulin action in young healthy males". BMC Endocrine Disorders 9 (3). doi:10.1186/1472-6823-9-3. PMID 19175906. 

[edit] External links

Retrieved from "http://en.wikipedia.org/wiki/High-intensity_interval_training"