Less Can Be More, Research Shows: Maximizing Health Benefits of
Exercise By Finding Your “Goldilock’s Zone”
October 12 2012
By Dr. Mercola
One of the biggest hurdles people face in maintaining an
exercise program is finding the time to do it. Fortunately,
modern exercise research shows that you can significantly
reduce your workout time while reaping better
health benefits, compared to a traditional cardio program.
The key is Peak Fitness or
high-intensity interval training (HIIT), which also goes
by other terms such as anaerobic, or burst training, which
I've discussed on numerous occasions over the past couple of
years.
However, recent research throws yet another twist into
the discussion about exercise intensity, time, and
subsequent effects.
Danish researchers were quite surprised when they
realized that exercising for less amount of time (even
without using high-intensity type training) still
produced greater weight loss, without making any planned
dietary changes.1
According to the old adage, the more calories you expend
during exercise, the more weight you should lose. But for
many, this theory never seemed to hold true, as they
continue to struggle with their weight despite spending
several hours a week at the gym.
We now know using HIIT can give you better results in
40-60 minutes a week compared to 5 hours of conventional
aerobics. But here, the major surprise was that 30 minutes
of exercise beat out 60 minutes of exercise at the same
weekly frequency, in terms of weight loss!
Finding Your Goldilock's Exercise Zone
The evidence suggests there may be a type of "Goldilock's
Zone" when it comes to exercise. "Just enough" exercise
boosts your overall energy levels, spurring you to be more
active during non-exercising hours (taking stairs, getting
out of your office chair more frequently, walking longer
distances).
"Too much" exercise might actually lead to an
increasingly sedentary lifestyle outside of exercise hours,
most likely due to a combination of exhaustion and
inadvertently eating or snacking more to compensate for the
high calorie expenditure during exercise. ("Too little" or
"none" will obviously not do you any good at all.)
You may recall I recently wrote about a study that
concluded
exercising in the morning did not lead to
increased food intake or food cravings, which seems to be in
direct contradiction to the findings in today's featured
study. But let's keep in mind that "the devil is in the
details."
In the current study, mildly overweight men who exercised
at a moderate pace for about 30 minutes (until they'd burned
300 calories based on their individual metabolic rate)
experienced a boost in energy and overall activity levels,
and did not increase their food intake. Obese women who
exercised at moderate to intense pace for 45 minutes in the
morning were also found to be more energetic and active
during non-exercising hours, and did not subsequently
increase their food intake either.
The men who sweat it out for 60 minutes instead of 30,
however, did not increase overall activity levels
during non-exercise hours, and they ended up eating
more. As reported by the New York Times:2
"At the end of the 13 weeks, the members of the
[non-exercising] control group weighed the same as they
had at the start, and their body fat percentages were
unchanged, which is hardly surprising.
On the other hand, the men who had exercised the
most, working out for 60 minutes a day,
had managed to drop some flab, losing an average of
five pounds each. The scientists
calculated that that weight loss, while by no means
negligible, was still about 20 percent less than
would have been expected given the number of calories
the men were expending each day during
exercise, if food intake and other aspects of their life
had held steady.
Meanwhile, the volunteers who'd worked out for
only 30 minutes a day did considerably
better, shedding about seven pounds each,
a total that, given the smaller number of calories that
they were burning during exercise, represents a
hefty 83 percent 'bonus' beyond what would have been
expected..." [Emphasis mine]
Finding Your Sweet Spot Includes Knowing Which Foods to Eat
and Which to Avoid
In summary, the researchers concluded that the shorter
exercise session appears to have allowed the men to "burn
calories without wanting to replace them." Combined with
greater activity levels at work and off-hours, the
overall health effect generated was greater than in
those whose workout sessions were longer, simply because the
latter didn't experience the same boost in off-hour energy
levels, and ended up eating more.
But another important factor not touched on in this
research is the effect of the types of food you
eat, before and after exercise. The study participants were
not given any particular diet; they were simply asked to not
alter their normal fare.
It's well worth noting that your choice of
breakfast food may play a significant role in decreasing
or heightening sensations of hunger afterward, which will
affect your overall calorie intake for the day – not to
mention how foods can alter your metabolic functioning, and
either for the benefit or detriment to your weight loss.
For example, eating carbohydrates for breakfast will
inhibit your sympathetic nervous system (SNS) and reduce
the fat burning effect of your exercise. Instead, it
activates your parasympathetic nervous system (PSNS), which
promotes storage of fat – the complete opposite of what
you're aiming for. Avoiding
fructose and other grain carbohydrates is a critical
element of a successful weight loss strategy. This includes
sports or energy drinks and fruit juices (even if they're
freshly squeezed).
Additionally, it would be wise to consider
skipping breakfast. You can review the article I
recently wrote on this
here. This is a form of intermittent fasting and I
believe it is one of the most profound new developments in
weight loss management. This can radically improve your
ability to shift to fat burning mode and effectively burn
fat rather than glucose. Also, when you exercise in a fasted
state you tend to have your cells rebuild and repair or get
younger.
Diet Also Affects HGH Production if You Do Interval Training
Furthermore, if you're doing high intensity interval
training you will naturally boost your production of human
growth hormone (HGH) – a fat-burning, muscle-boosting
hormone – but if you consume fructose within two hours of
exercise, you will effectively negate this highly
beneficial effect. In essence, if you don't pay attention to
your diet, you may be wasting an awful lot of time in the
gym.
As explained by HGH Magazine:3
"A high sugar meal after working out, or even a
recovery drink (containing high sugar) after working
out, will stop the benefits of exercise induced HGH. You
can work out for hours, then eat a high sugar candy bar
or have a high sugar energy drink, and this will shut
down the synergistic benefits of HGH.
...If you miss reaching HGH release during
working out, you will still receive the calorie burning
benefit from the workout. However, you'll miss the HGH
'synergy bonus' of enhanced fat burning for two hours
after working out.
This is an extremely important fact to remember
if you want to cut body fat and shed a few pounds.
...[Research has] demonstrated that carbohydrates are
burned during exercise in direct proportion to the
intensity of training. Fat burning is also correlated
with intensity. However, the actual fat burning takes
place after the workout, during the recovery. This makes
the 'Synergy Window,' the 2 hour period after a workout,
very important in maximizing HGH, once it's released
during exercise."
Another 2010 study in the Journal of Applied
Physiology4
showed that eating a low-carbohydrate meal after aerobic
exercise enhances your insulin sensitivity. This of course
is highly beneficial, since impaired insulin sensitivity, or
insulin resistance, is the underlying cause of type 2
diabetes and a significant risk factor for other chronic
diseases, such as heart disease.
So, while exercise is very effective for enhancing
insulin sensitivity, the type of foods you eat plays a
significant supporting role. Eating a high sugar meal after
exercise will simply not allow you to reap the maximum
benefits from your workout, regardless of what type of
exercise you engage in.
Good, Better, Best
As you can see, optimizing your health and weight
involves a number of factors, and all of them need to be
given appropriate consideration. Poor diet with a strenuous
exercise regimen will surely leave you disappointed, just as
a healthy diet with improper or no exercise will leave most
people wanting. It's worth noting though that about 80
percent of the health benefits you get from a healthy
lifestyle come from your diet. The remaining 20 percent is
derived from your exercise – but it's an important 20
percent! It's really about synergy.
That said, abstaining from food altogether for certain
periods of time, known as
intermittent fasting, can actually boost exercise
results even more.
I've previously interviewed fitness expert Ori Hofmekler
on the issue of fasting and exercise. According to Ori,
fasting actually has the surprising benefit of helping you
reconstruct your muscles when combined with exercise. This
is due to an ingenious preservation mechanism that protects
your active muscle from wasting itself.
In a nutshell, if you don't have sufficient fuel in your
system when you exercise, your body will break down other
tissues but not the active muscle, i.e. the muscle
being exercised. That said, neither Ori nor I advocate
starvation combined with rigorous exercise. It's important
to be sensible. And you need to consume sufficient amounts
of protein in order to prevent muscle wasting. While most
people need to address the foods they DO eat before
considering skipping meals, intermittent fasting can provide
you with many benefits, and is another tool you can
experiment with to help you reach your goals.
One of the mechanisms that makes intermittent fasting so
effective for weight loss is the fact that it – like HIIT –
provokes the secretion of HGH. It also increases
catecholamines, which increases resting energy expenditure
while decreasing insulin levels, which allows stored fat to
be burned for fuel. Together, these and other factors will
turn you into an effective fat-burning machine –
especially if you incorporate it with high intensity
interval training.
How to Safely Combine Intermittent Fasting with Exercise to
Boost Weight Loss
In essence this fitness-enhancing strategy looks at the
timing of meals, as well as when NOT to eat. This isn't one
of those fad plans, where you eat just one or two things for
several days in a row. Instead, intermittent fasting simply
means restricting your food intake during the day to a
smaller time window (typically six to eight hours). If
that's still too difficult, restrict your food choices to
light raw foods, vegetable juice and/or whey protein or
eggs, but aim for having just one main meal a day, in the
evening.
When you add exercise to the mix, you complete your
workout while fasting, but this must be
followed by a recovery meal within 30 minutes of your
workout. The easiest way to do this is to exercise in the
morning on an empty stomach, followed by a recovery meal
half an hour later. Then you fast until the set time window
designated for eating, followed again with fasting during
late-evening/overnight hours and into the morning, until 30
minutes after exercise the next day.
Naturally, if it's a non exercise day, you don't need the
recovery meal. But on exercise days, a recovery meal is
critical and should NOT be skipped in the name of fasting.
Whey protein is ideal, as it is fast-assimilating and will
provide you with the nutrients your muscles need for
recovery. (Make sure to avoid all sources of fructose for
the reasons discussed earlier). Skipping the recovery meal
after exercise is very ill advised, as it can lead to brain
and muscle damage.
Why Exercise and Fasting Makes for a Beneficial Duo
Exercise while in a fasted state results in acute
oxidative stress, and while this may sound ominous it
actually benefits your muscle by keeping your muscles'
mitochondria, neuro-motors and fibers intact. Chronic
oxidative stress, on the other hand, is very detrimental and
can lead to disease. As explained by fitness expert
Ori Hofmekler:
"[Acute oxidative stress] is essential for
keeping your muscle machinery tuned. Technically, acute
oxidative stress makes your muscle increasingly
resilient to oxidative stress; it stimulates glutathione
and SOD production in your mitochondria along with
increased muscular capacity to utilize energy, generate
force and resist fatigue.
Hence, exercise and fasting help counteract all
the main determinants of muscle aging. But there is
something else about exercise and fasting. When
combined, they trigger a mechanism that recycles and
rejuvenates your brain and muscle tissues."
The mechanism he refers to is triggering genes and growth
factors, including brain-derived neurotropic factor (BDNF)
and muscle regulatory factors (MRFs), which signal brain
stem cells and muscle satellite cells to convert into new
neurons and new muscle cells, respectively. This means that
exercise while fasting may actually help to keep your brain,
neuro-motors and muscle fibers biologically young. The
combined effect of both intermittent fasting and short
intense exercise may go way beyond helping you to burn more
fat and lose weight; it may help you to:
Turn back the biological clock in your muscle and
brain |
Boost growth hormone |
Improve body composition |
Boost cognitive function |
Boost testosterone |
Prevent depression |
Cut the Correct Calories!
Intermittent fasting (IF) makes your dietary choices all
the more important. Please do not embark on intermittent
fasting if your diet consists primarily of processed and/or
fast foods! This is because it's not restricting calories
per se that does the trick, but rather it's the restriction
of unnecessary calories from foods that do not supply
essential nutrients.
It's important to realize that all calories are NOT
created equal, and will not have identical effects your
weight or health.
Their value depends on the types of food (nutrients)
they're attached to. You barely need any grain carbohydrates
in your diet. You could cut out virtually all sugar and
grains, limiting carb calories to vegetables (and perhaps
some less harmful
starchy carbs like potatoes and rice) and still thrive.
Unfortunately, in the US, six of the top 10 sources of
calories are carbohydrates from sugars and grains,5
and this is a major reason why so many Americans are
overweight. They're simply eating far too many sugars. So
it's very important to restrict carbs when doing a
calorie restrictive diet. When you cut out the sugars and
carbs it is wise to replace them with high quality
non-processed fats. Some of my favorites include:
- Organic grass-fed raw butter
- Eggs
- Coconut oil
- Avocados
- Almonds
There's very compelling evidence showing that calories
from healthy fats are far more beneficial for your
health than calories from carbohydrates. And fear not...
It's already been well established that stearic acid (found
in cocoa and animal fat) has no effect on distorting your
healthy cholesterol ratios at all, and actually gets
converted in your liver into the monounsaturated fat called
oleic acid.
The other two, palmitic and lauric acid, do
raise total cholesterol. However, since they raise
"good" cholesterol as much or more than "bad" cholesterol,
you're still actually lowering your risk of heart
disease. And there are additional benefits. Lauric acid (as
from coconut oil) has been shown to boost thyroid hormone
activity along with your body's metabolic rate. This is
obviously a huge advantage to those interested in weight
loss or those who suffer from an underactive thyroid.
I couldn't encourage you more to implement this program.
It has radically improved my personal confidence in using
diet choices to achieve high level wellness and optimal body
fat. Cutting down on your grains and sugars, replacing them
with high quality fats and skipping some meals, especially
before exercise, seem to be a powerful combination to help
you take control of your health.
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