What is HIIT?
High Intensity Interval Training (HIIT) is commonly comprised of cardiovascular exercises characterized by the alternation of short periods of intense activity followed by a less-intense recovery period, also known as active recovery. It’s commonly used in team sports as an efficient training strategy to improve aerobic capacity without negative effects on strength, power and sprint performance.
Generally, HIIT is performed at 80-90% of maximal heart rate (HRmax) during the active intervals and 60-70% of maximal during the recovery phase.
There are different HIIT protocols with the aim to improve different energy systems. Firstly, there is the ratio 1:1 with 3 minutes of high intensity training followed by 3 minute of low intensity. This type of training can progress by modifying the duration (e.g. 5 Minutes) however must always be followed by an equal recovery time. Another popular protocol is the “Sprint interval training”, characterized by 30 seconds of sprint at the maximum personal effort followed by 4.5 minutes of low intensity exercise, repeated 3 to 5 times. Finally, the typical work is 1:3 ratio, with 15 seconds of high intensity exercise and 45 seconds of low intensity, typically last for about 8 rounds.
HIIT and tennis
For the characteristics of Tennis, HIIT seems to be an adapted exercise training to improve its performance. In fact, Tennis is characterized by high-intensity efforts alternated with low-intensity activity, when tennis players have to run, stop, twist, jump, slide, recover and hit in different directions. 6 weeks of HIIT, 3 times per week is suggested to have positive effects on VO2peak and on tennis-specific endurance. 
On the other hand, HIIT has to be integrated with specific strength endurance exercise protocols however with the implication of resistance training to the HIIT protocol this can be achieved.
In conclusion, HIIT improves VO2max, anaerobic threshold, hear rate recovery, stroke volume and Exercise Post Oxygen Consumption (EPOC), all of which are important elements of Tennis performance. HIIT can be easily incorporated when using the Technogym Excite® Bike, alternating 1’30’’ of cycling at 65% of HRmax with 30’’ of cycling at 85% of HRmax for 20’.
References
- Fernandez-Fernandez J, Zimek R, Wiewelhove T, Ferrauti A. High-intensity interval training vs. repeated-sprint training in tennis. J Strength Cond Res. 2012 Jan;26(1):53-62. doi: 10.1519/JSC.0b013e318220b4ff. PubMed PMID: 21904233
- ACSM information on High-Intensity Interval Training. Brochure content provided by Len Kravitz, Ph.D. 2014
- The Journal of Strength and Conditioning Research. Impact Factor = 1.978
