How can I lose weight by running?

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Some do it for aesthetical reasons, some for reasons of health – losing weight. Especially in spring, people try to get rid of some extra kilos. Can running help? Yes, if you follow some simple rules!

A lot of people are constantly concerned with how they can lose weight. It is commonly known that, in order to lose weight, you need to burn more calories than you eat. This can either happen through a reduced intake of food, or trough increased physical activity, by which we can burn more calories. It is all about the calorie balance, really. So, how can I achieve a negative calorie balance through running? And what do I have to take into account? Gommaar D’Hulst, Post doc in the Laboratory of Exercise and Health at the Department of Health Sciences and Technology, ETH Zurich, has helped us answer these questions.

1) In what way does running help people to lose weight?

Increasing your energy expenditure by any form of physical activity, including running, can help to decrease body weight.

2) Can anyone lose weight with the help of running? 

Anyone can lose weight, as long as he/she expends more energy (kcals) than he/she consumes. The difference between people will be how hunger is regulated after (or in between) running sessions. People who get very hungry and compensate for the expended calories will have a harder time losing weight (more on this in question 6).

3) Can you continue eating normally when you start running (or run more than before) and still lose weight, or do you always have to change your eating habits as well?

No, you do not necessarily have to change your diet. It all depends where you come from. If you already eat healthy and stay away from processed food, there is no need for change. However, if you have an unhealthy diet, it might be worth to see a registered dietitian who can put you on the right track. A healthy eating pattern, of course, makes it easier to lose weight with running.

4) So, what do you think is the ideal diet if you want to lose weight but still have enough energy for running?

Adherence is the most important thing in any diet. If you want to choose a diet, choose one you can stick to. However, as already mentioned, I would not drastically change much when the eating pattern is already healthy. By healthy I mean 35-40% carbs, 25-30% fat, 1.4g/kg protein, little sugar and a varied eating pattern. I am not in favour, and also the research is inconclusive, in completely deleting one macronutrient (like carbohydrates).

5) Is it true that you lose weight faster if you don’t eat anything a few hours before and after your runs?

This is a slippery slope since this kind of eating pattern can induce food cravings (and weight gain). Another route worth considering is intermittent fasting. Here you will have all your food intake in 8-10h time-span, for instance from 9AM to 7PM. Research is very positive (certainly in animals) about intermittent fasting. In fact, even when total calories were matched, metabolic health parameters such as the sensitivity to insulin and certain liver parameters are positively influenced by intermittent fasting. This is certainly an interesting area of research, but the combination of intermittent fasting and exercise are not fully elucidated yet.

6) Is there any formula for how many calories you burn by running?

There are probably a lot, but here is one:

MEN: Calories Burned = [(Age x 0.2017) + (Weight x 0.09036) + (Heart Rate x 0.6309) — 55.0969] x Time / 4.184.

WOMEN: Calories Burned = [(Age x 0.074) — (Weight x 0.05741) + (Heart Rate x 0.4472) — 20.4022] x Time / 4.184.

However, I personally think these formulas are mostly nonsense because there are big differences between people (large standard deviations). Generally, people tend to think that they burn more than they actually do. That is, the food compensation after a run (or other type of activity) is often too high, by which the negative calorie balance is destroyed. This is something people MUST be aware of if they want to lose weight.

7) Will your body at some point adapt to increased physical activity and not burn calories as fast anymore, like it is with diets sometimes?

There is some data indicating that very active people unconsciously adapt to the increased physical activity in two ways: 1/ they start moving around less, decrease ‘fidgeting’ and 2/ get more efficient in using the energy for a variety of bodely functions such as food digesting and immune system, thereby decreasing basal metabolic rate (what you burn in a resting state). Moreover, one of the adaptations to exercise is that the muscle will be more efficient in producing energy for a given amount of oxygen. So, after a while, people will burn less calories for a given speed than before (also because they lose body weight and therefore use less energy to move their body). Thus, in order to keep the weight loss going, a person will have to run slightly faster (and longer) over time (or, of course, eat less).

8) Is it better to run fast, slow, for a short or a long period of time if you want to lose weight?

In general, it does not matter much. Losing weight is almost exclusively determined by energy balance. Some people will like interval training more, while others will opt for long easy runs. Again, it all comes down to adherence. Of note, because the intensity is higher, interval training will burn as many calories as longer slow runs, making it perhaps a more time-efficient method for losing weight.

9) What role does your heart rate play in terms of what your body burns or how fast?

Heart rate will be an indication for when the body is in the ‘aerobic’ zone (low HR) or in the more anaerobic (high HR) zone. So, it is a good measurement of intensity.

However, that you have to stay in the ‘easy’ zone to lose weight is a myth. Let me explain briefly by the following graph:

   

It represents fuel utilization at different exercise intensities, 40% is easy and 75% is hard. While muscle glycogen and plasma glucose are carbohydrate related energy sources (sugar taken from the muscle and blood), muscle and plasma TG (triglycerides within the muscle or derived from the blood, “other fat sources” in the graph) and plasma FFA (blood derived fatty acids) are fat related energy sources. As it is true that at easy pace you are RELATIVELY burning more fat (around 50% carbs and 50% fats) compared to running fast (85% carbs and 15% fat), ABSOLUTELY you are still burning less or the same amount of fat than when you are exercising at harder paces. In fact, at a harder pace, the relative contribution of carbohydrates is increased and together with the fact that you are expending more energy, you will 1/burn more or a similar amount of fat and 2/ burn way more carbohydrates at high intensities as compared to lower intensities.

A side effect of high intensity training this is that the emptied energy stores will have to be refilled and your body has to recover more from a hard run. The body thus taps the energy savings in form of fat. The aerobic energy systems (fat burning) will thereofre be increased the hours after a hard training session, meaning that your body is still burning more calories than normally when at rest. This will positively influence the energy balance for weight loss.

10) Is there a certain time of the day which is best for our body to run in order to lose weight?

There is recent research indicating that PM exercise might be better performance wise, but these studies did not look into weight loss. Fasted training (after a long period without food intake, i.e. before breakfast) is popular indeed, because the body will learn to rely more (albeit slightly) on free fatty acids (fat) for energy and it will increase metabolic pathways which rely more on fat oxidation (mitochondria and select enzymes). BUT: Solely because the body gets better in metabolizing fat, that the person will NOT lose fat more quickly! You still only lose it when your overall energy balance is negative. Think about it, it is similar as with the ketogenic diet. On the ketogenic diet, you will oxidize (burn) more fat, than on a normal diet, BUT you also take in much more fat. Thus, again, it winds down to energy balance, on the ketogenic diet or when training fasted, you can gain weight if you eat more than what you expend.

11) Should one combine running with a different form of exercise in order to achieve the biggest effect?

I would suggest that strength training should always be incorporated in a training scheme of a runner. Not only because its possible beneficial effects on losing weight, but most surely because of its effect on injury prevention. Stronger muscles, together with better biomechanics will have a positive effect on the longevity of a runner’s career. Additionally, proper strength training can lead to a more favourable body composition, meaning more muscles and less fat. On the long term, this will result in a slightly higher resting metabolic rate and thus more efficient weight loss.

 

Gommaar D’Hulst studied Sport Sciences and Biomedical Kinesiology at the University of Leuven, Belgium where he also gained his PhD. Currently he is working as a post-doctoral researcher at state-of-the-art “Exercise and Health” lab at ETH Zürich where his research concentrates on topics like muscle health and nutrient sensing. In his spare time you can find him in CrossFit Kreis9 for his daily Workout Of the Day. Follow Gommaar and his colleague Henning Langer on their Instagram-Account (@wod_science) for daily posts about the science behind strength training, endurance and CrossFit.

 

Edited  by: Marion Aebi

Burning fat – but how?

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The ideal fat burning pace does not mean that you burn the most fat at that speed. Myths and facts about fat burning.

It is easier than you think: With slow trainings the economy of the fat metabolism is trained, with intensive and fast units most calories and therefore the most fat is burned in absolute terms. There are two different forms of training with two different objectives.

No weight loss without a negative energy balance

Let’s start with weight loss. If you want to reduce fat, you have to work on your energy balance. What you put into your body also has to go out again, otherwise the fat pads will swell out of the trousers. Unused calories are stored by the body as fat. The energy balance is therefore the decisive criterion for losing weight. Only when input (calories consumed with the diet) minus output (calories burned) is negative, i.e. the energy consumption is greater than the energy intake, only then do we lose weight.

One can increase the output with increased exercise or decrease the input with a cleverly planned diet. There are two starting points when it comes to contributing to weight loss through sports. Either you can try to burn as many calories as possible in a short time. The motto here is: Whoever wants to burn as many calories as possible also has to put in their maximum effort. Or one increases the duration of sports and adjusts the intensity to become able to sustain a pace for as long as possible, which is possible only with a middle intensity. Here, not predominantly the carbohydrates are needed for the energy supply, but – by means of oxygen – also fat is used.

In percentage terms, the less intense the physical activity, the more fat you burn. Therefore, this intensity level is often referred to as the “fat burning zone”. However, this only applies as a percentage, because due to the low total energy turnover, the absolute amount of burned fat in the fat burning area is still lower than when you are doing intensive trainings.

Fat metabolism for more economy

The training mode in the low “fat burning zone” has another special meaning in endurance sports. The burning of carbohydrates (= glycogen burning, sugar burning) provides about twice as much energy per time as the burning of fat, but the fats burn for much longer and are practically available without limit in the body. The glycogen reserves are only sufficient for a strain of about 90 minutes.

A regular training in the moderate fat metabolism zone is therefore the essential foundation the other trainings can be built on. In addition, less intensive training sessions require less regeneration time and can be repeated more often.

By accessing the fat metabolism, our body improves the more economical of the two main metabolic processes in endurance sports. This can protect the glycogen reserves, which are only available in limited quantities. With the fat metabolism, one can run for hours to days – with the glycogen metabolism in the best case one to two hours without refilling carbohydrates. The better the fat metabolism is trained, the more it helps to preserve the carbohydrates from the start and to maintain the desired speed longer at the end. And the less you will fall into that dreaded “bonk” from one moment to the next.

What are the benefits of metabolic training?

The training of fat metabolism makes sense not only for (marathon) runners, but for all endurance athletes who perform during long trainings. Cyclists and triathletes also explicitly train their fat metabolism during the preparation for the upcoming season. The longer the strain during competition, the more important it becomes. Fat metabolism training improves long-term endurance. The organism forms more blood in order to transport oxygen more efficiently, the number of energy power stations of the muscles (mitochondria) increases, so that the cells can gain energy even better. By adapting the organism, the body can process training strains more quickly. And last but not least, in addition to the muscles and blood, the cartilage surfaces, tendons and ligaments also develop, so that the training can be better coped with and is better protected against overloading.

When does metabolic training start?

The fat metabolism is demanded at almost all intensities. But only when the duration of the strain is long and the intensity is chosen to be low we can actually speak of a classic fat metabolism training. Long units from 60 up to 180 minutes (depending on your goals) should be planned once a week in running. In combination with other extensive endurance runs, this builds the necessary foundation. The extensive units are supplemented by intensive training in a ratio of 1:3. Every third extensive unit is followed by intensive training.

If you want to be successful, you should invest in fat metabolism training all year round. The positive thing about this is that these training sessions are not very intensive and are only challenging due to their long duration. In order to break through the monotony somewhat, it is recommended to do the long round with training colleagues or to do a new round every now and then.

Examples of fat metabolism trainings

  • Long jog: Long slow run up to 3 hours if the goal is to do a marathon. Otherwise you can also do “only” 80 minutes up to 2 hours. Motto: The slower, the better!
  • Long run: Long, brisk run (90% of the marathon speed) up to 3 hours or a maximum of 38 kilometers in the specific preparation for a marathon. In the case of shorter distances up to 2 hours or a maximum of 28 kilometers.
  • Cross-training: Long strains in one or more alternative sports with low intensity. Example: 3 hours cycling or 5 hours hiking. Ideally, a short running workout of 30-45 minutes is added at the end to enable the transfer to the target discipline (running).

The two metabolic systems fat metabolism and carbohydrate metabolism are always both involved in endurance strains, but not to the same extent. During intensive exercise, carbohydrate metabolism is primarily used; with increasing training duration and a lower pulse rate, fat metabolism makes up the largest proportion of the energy supply. Training in the ideal fat burning area does not mean burning a maximum of calories (more calories are burned during intensive training than during loose training) but improving the economy of the fat metabolism with low intensities so that it can also participate in the energy supply during more intensive training.

This blog post by Andreas Gonseth was provided by Fit for Life. Fit for Life is the Swiss magazine for fitness, running and endurance sports.

Performance diagnostics for runners

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Performance tests are not only for professional athletes. Even beginners and athletes with little free time often get important insights from taking them.

Author: Raphael Huber, MSc, Movement and Sports Science, MAS in Nutrition & Health, Medbase Winterthur WIN4

 

 

Where do I stand in my training? How well is my general fitness? How do I train most efficiently despite little free time? And what is the best way to achieve my goal, for example, the half marathon? Those who ask themselves questions like the ones above are candidates for performance diagnostics since it provides the most accurate answers.

Performance diagnostics comprises two categories: Endurance and strength diagnostics. The core element is a lactate level test. Most athletes do it on a treadmill or bicycle ergometer, rarely on a rowing ergometer or while swimming. Every three or five minutes, the speed or resistance is increased – until the athlete can no longer do it or no longer wants to continue.

Ideally, the performance level test measures three components

  • the fitness of the cardiovascular system
  • the subjective perception of stress
  • the metabolic state

The continuous measurement of the heart rate during the performance test shows how trained the heart is. At the same time, the athlete should indicate at the end of each performance level how resilient they still feel.

The “Borg Scale”, named after the Swedish physiologist Gunnar Borg, serves as a measure for the perceived exertion. Six as the lowest value of the scale corresponds to a very light strain, the highest of twenty is the effort at which the athlete reaches their limit which can’t be maintained for long.

The performance test is most meaningful if the lactate concentration in the blood is analyzed as well. Lactate (lactic acid) is produced as soon as the oxygen supply through respiration is no longer sufficient for energy production in the muscle. As a result, muscle cells increasingly switch from aerobic to anaerobic energy production, which is reflected in a sharp increase in the lactate concentration. To determine this, it is best to extract one drop of blood per performance level from the earlobe. Such a performance diagnosis takes about 1.5 hours (including training advice) and costs around 250 Swiss francs.

Individual training areas

The measured values – heart rate, subjective perception and lactate – can be used to determine when the runner is still training in the range of their basic endurance, when the aerobic (first lactate increase) and anaerobic threshold values are reached and when the athlete starts running in the interval range. This varies from person to person.

If, for example, the heart rate and lactate values are already high, but the perceived exertion is still in the middle range, this may indicate that the athlete tends to “bite their way through”. Those runners are mentally strong but often overtax their bodies.

Athletes who know their performance values, strengths and weaknesses can focus their training on what is important for their type of sport: Marathon runners, for example, need a good basic endurance, while 800-meter runners have to cope with high lactate values.

Good long-distance runners have low lactate values (about one millimole per liter of blood, mmol/l) in the test over several performance levels. This is partly due to the ability of their muscles to produce less lactate at a given level and partly due to the fact that their body can recycle the lactate more easily.

For good short-distance runners, on the other hand, lactate levels rise faster. However, their organism is able to continue to perform at its best despite high values of over ten mmol/l. In technical jargon, this is called “good stamina”.

Without knowledge of the individual thresholds one– in the truest sense of the word –  runs the risk of training incorrectly. This is all the more serious when the time budget is tight. If you train for a marathon alongside work, family, and commitments, it is essential to manage your time very well. Here, the performance test can help to make the training efficient and goal-oriented. The running.COACH training plan is adjusted to your individual threshold for you to train in the right training areas.

Test results and nutrition

The training plan also helps to coordinate nutrition. As long as the training is within the range of basic endurance, the body primarily uses fat reserves as a source of energy. At this stage, there is no need for an extra portion of pasta providing carbohydrates. In high-intensity training, on the other hand, the organism can hardly burn any more fat reserves. In this situation, a “low carb” diet makes it difficult to achieve the required performance.

A performance test makes sense also for amateurs and beginners

Knowing where one’s own thresholds are thus makes sense for several reasons – not only for competitive athletes but also for amateurs and especially beginners. They in particular often make the mistake of expecting too much of themselves according to the motto “Only hard training is good training”. If this happens too often, the “basis” is neglected, and the risk of injury also increases.

The right training is one that is adapted to the individual organism. And this can best be determined by the performance test.

RULE OF THUMB

A rule of thumb can help to determine the performance areas:

  • Basic endurance 1: The athlete can still talk normally without getting out of breath
  • Basic endurance 2: Only short sentences are possible
  • Threshold range: “Yes/No” only
  • Interval range: Speaking is no longer possible