High intensity interval training (HIIT) is a training method that requires participants exercise at 80%-95% of the maximum heart rate predicted for their age. Many HIIT programs do not monitor heart rate, so it’s possible that participants are working at higher intensities.
The recovery period can last as long as the working phase, and is usually performed at between 40-50% of a person’s estimated maximum heart rate. Again, this feature of HIIT may not be controlled if heart rate monitors were not used.
HIIT has many advantages.
- The intense recovery requirements are what delivers the aerobic benefits. For a Personal Trainer Cheltenham, visit Inside Sweat
- Resting blood pressure is improved
- Reduces the risk of coronary heart disease and improves cardiovascular health
- Insulin sensitivity increases, making glucose available for exercise
- Enhance cholesterol levels
- Increases metabolism both during and after
- Maintaining muscle mass while reducing body fat
- The point of fatigue onset is delayed during periods of lower intensity exercise
- Post-exercise, HIIT produces a greater effect on metabolism
Main Disadvantages Of HIIT
- This is a very strenuous workout and not recommended for those who are unfit
- Vomiting and nausea may occur
- Extreme discomfort when exerting yourself
- Blood pooling can occur when you make rapid changes to your body position
- Post-exercise muscle soreness is high
When performed in excess, rhabdomyolysis can occur. This is the breakdown and release of the contents of the muscle fibres into the blood. These substances can damage the kidneys and are dangerous to them.
HIIT training is widely used and can help personal trainers achieve their clients’ health, fitness, performance and body transformation goals but only under strict observation.
How interval training may slow ageing
Research published by the Mayo Clinic found that high intensity interval training did more than other forms of exercise to delay the ageing process. Researchers reported that it changes the DNA in our cells to boost the energy our muscles produce, and it can encourage the growth of new muscle, which we tend to lose as we get older.
The study compared people aged 18 to 30 with people aged 65 to 80, following either strength training or interval programmes. The strength group gained more overall muscle mass, but the interval group improved more at a cellular level. The change was most striking in the older participants, who also saw better heart and lung function and insulin levels, and in some cases the deterioration of muscle cells was reversed.
You do not need to be very fit to start. Simply increasing the intensity of your walking is enough to begin, but check with your doctor before taking up a new exercise routine.
Warming up properly before a HIIT session
Working at high intensity makes a warm-up essential. A good warm-up is low-intensity movement that gradually raises your heart rate, breathing, body temperature and blood flow, so your body is ready before the hard intervals begin. Five to ten minutes is generally enough, though more intense sessions may call for a little longer.
Dynamic warm-ups tend to work best. They focus on large muscle groups and copy the movements you will use in the workout, which helps activate the muscles and primes the connections between nerves and muscles. Compared with a gentle, static start, they do more to prepare the body for sudden bursts of effort.
The main benefit is a lower risk of injury. Warmer muscles are more elastic, carry less tension and cope better with high-intensity movement, while the heart is eased up to working levels without being overtaxed. Think of it like letting a car warm up on a cold morning before asking it to work hard.