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High-intensity interval training (HIIT) has been shown to elicit amazing health benefits in minimal time , since “ I don’t have time ” is the mostly cited excuse for not working out - interval training it appears not only takes up less of your time but also ramps up health benefits .

Interval training has a huge beneficial response on the heart , the lungs, bone density ,muscle tissue and energy levels . Optimising hormones, helping with menopause symptoms, PCOS, the heart and heart related conditions, lungs and generally improving over all health biomarkers helping to lower biological age and mortality risk.

Exercise but specifically interval training has a huge benefit on the brain ( increasing lactate ) through something called BDNF( Brain derived Neurotropic Factors )- or ´feel good´ hormones ´.

BDNF improves memory and cognitive function and therefore can help reduce risks from or symptoms of neurological diseases like Parkinson’s and altzhimers , schizophrenia, depression and autism

Interval training quickly takes blood glucose out of the circulating blood by the muscles ,reducing our blood glucose levels ( helping metabolic diseases and type II diabetes ) increasing our energy allowing us to work out more intensely and by increasing our energy stores - allowing us to work out longer and have more energy in general .

Interval training has a positive effect on body composition - through intensity and energy demands it burns calories at work and then continues to burn fat for up to 48 hours after the session - although this is a small after effect the accumulation of this over time is very positive .

Finally if I have not yet sold it to you - its is adaptable to any form of exercise from walking, to biking, swimming to resistance training , simply put any form of movement that you can use to get your heart rate up

So what does interval training mean ? In a nutshell , elevating your heart to as high as you can in short periods or “ intervals ” ( Note : do this safely : warning warning if you are new to exercise, elderly or have a health condition consult with your physician or health care advisor ).

After 4 months of walking intervals instead of just walking benefits were shown to reduce type II diabetes , reduce blood glucose, Increase cardio respiratory and increase fat loss.

Your rest interval is usually characterised by sufficient time in order to be able to repeat the interval with the same perceived effort . Or alternatively try ´exercise snacks ´which refers to one effort of 1 minute of exercise only but repeated 1 or more times during the course of the day .

A 1 minute burst of vigorous effort a couple of times a day - air squats , burpees etc - is enough of a stimulus to improve VO2 max or max heart rate ( fitness level and efficiency of your heart ) - and works cumulatively over the course the day

“ Just a 1 minute burst of vigorous effort a couple of times a day - air squats or burpees - this type of stimulus is enough to stimulate VO2 max or heart rate - and works cumulatively over the course the day “

Exercise snacks are a great way to break up a sedentary day. Where the exercise minute can fit into your day rather than trying to plan your day around squeezing in an exercise session .

Using this exercise snack method - In a study with 25 000 people who exercised at just 3-4 Minutes of interval training a day , results showed they reduced their risks of heart attack , cancer and all cause mortality by 30% - this is less than 30 minutes per week !

When the exercise was raised to 9 minutes a day there was a 50% decrease in cardio vascular disease and 40% decrease in cancer !

Using the repeated shorter intervals - your work or exercising interval effort will be different depending upon factors like your age, your work out history, your genes , your natural VO2 max - hang - on if I am already losing you don’t worry these terms are not relevant to know ( if you want me to explain them I am happy to do so but you do not need to know the science in order to start this protocol )

Your work interval will be intuitively short because you will not be able to sustain a high level of activity for a long period of time. This work and rest period can be flexible depending on you and your goals.

Working this into the course of your day can quite simply be throwing in intervals of fast walking instead of simply walking , taking the stairs instead of the elevator , doing a 1 minute interval of for example body weight squats during the course of your day.

The rest period meanwhile on repeated efforts is governed by the amount of time it takes you to recover and can vary from 10 seconds to 3 hours !

The biology behind the interval - as compared to the long hours of steady state aerobic training is the simply the shock to he body . Causing an imbalance to the homeostasis that the body works hard to keep .

The greater degree of impact or imbalance ( stress ) of the exercise to the body ( by manipulating exercise time, rest time , intensity and number of intervals ) the more dramatic the change the body responds to.

It is In this way interval training works differently to Long steady aerobic bouts of exercise because it induces more stress in a shorter period of time but achieves the same or in some cases better effects.

“ High intensity cycling for 6 minutes increased the amount of BDNF 5 times more than longer sessions of low intensity cycling “Medical news today ( relating to a 6 fold increase in lactate levels )

Stress leads to adaptation in the body .

As previously mentioned - a word of caution , if you are new to exercise or suffer health problems or are elderly because indeed all of you can benefit from this style of training - then introduce intervals in a very gentle way

I recommend wearing a heart rate band ( polar or garmin are the best ) . There are all kinds of tests you can perform to work out your improvements . The easiest strategy is that when you do the same interval for the same time period at the same exertion your exercising heart rate is lower ( because it has improved its efficiency ) and your recovery heart rate - otherwise measured by your heart rate returning to its normal rate - is quicker.

In summary - because of the amazing adaptions of the body in a fairly short period of time and the adaptability to any mode of exercise this style of training can be used for almost anyone. These physical adaptions will continue to happen as long as we continue to use the protocol.

Over time the body responds to the increased demands of the interval activity by increasing our energy stores giving us more energy at work and at rest and making our bodies and brains work more efficiently

“ Using a protocol of 1 minute warm up and 1 minute cool down and 3 x 20 second interval bursts of activity , 3 times a week , there is a 1 met improvement ( i.e 10% boost in cardio respiratory fitness ) “

Other exercise protocols :

10 x 1 minute workout : 1 minute on : one minute off Intervals , 3 times a week .

“ 1 minute hard , 1 minute easy repeated 10 times improved blood glucose throughout the course of the day especially after meals ”

5 x 1 minute workout intervals

Body weight muscular sessions of 15 - 20 sets which last 20 minutes to 30 minutes

“ Interval training on body composition : increase lean mass and reduction in fat mass. You can see changes in 6 weeks”

In short any exercise interval is beneficial, regardless of age since being sedentary or sitting for extended periods of time increases obesity, blood pressure, cholesterol and blood sugar levels.

Try to incorporate exercise intervals into your day on a regular basis and not only will you feel happier , but your body composition levels ( especially if you follow a healthy nutritional plan )will also be positively impacted along with your longevity .

If you need help starting out on a an exercise programme or you lack motivation then be sure and drop me a line .

Please follow me on instagram @katiehandysidetraining where I regularly post interval sessions along with on my YouTube channel : Katie Handyside@flatbellyin90days


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