Does going to altitude help you reduce fat mass?

Fat Metabolism at Altitude

Increases in the energy requirements of individuals, and the subsequent breakdown of energy stores such as fat, have been shown to result from time spent at altitude amongst both healthy and obese individuals. Thus, leading to the suggestion hypoxic physiology has the ability to induce favourable changes in weight and fat mass amongst a human population.

It may therefore be suggested that exposure to hypoxic conditions, or altitude, has the potential to serve as both a preventative, and treatment method against the growing problem of obesity in today’s society.

The exact mechanisms behind such reports however are largely unknown and continue to be debated due to the large number of confounding factors present during field work and expeditions. Factors including changes in diet, increased physical exertion, extremes in weather conditions and lack of food availability can all play a role in weight loss at altitude.

Moreover differences in findings within the previous research highlight the complex nature of inquiry and the difficulty in investigating the effect of hypoxia in isolation on these factors. Nevertheless such findings of weight loss and changes in body composition have been attributed to other physiological factors including suppression in appetite (leading to a subsequent decrease in food intake and thus a negative imbalance in the energy equation) and biochemical alterations in fat and carbohydrate metabolism. Perhaps more importantly, previous research has also attributed a major part of these losses in weight to reductions in fat mass further supporting the potential for use in a health and clinical setting in which a loss of fat mass would be beneficial.

One of the physiological investigations being carried out during our time in Peru intends to address such an issue with weight loss, taste sensation, energy expenditure and fuel utilisation (the amount of fat, carbohydrate and protein used to fuel our bodies) all being measured at different stages of the trip. The investigation aims to answer the following research questions;

1.      Does an eighteen day exposure to hypobaric hypoxia have a significant effect on an individual’s body weight?

2.      Does exposure to hypobaric hypoxia alter the energy expenditure and fuel utilisation of healthy individuals?

3.      Does energy expenditure and fuel utilisation alter throughout differing stages of acclimatisation to hypobaric hypoxia?

4.      Is there a lasting effect of altitude exposure on energy expenditure upon return to sea level?

During our 18 day stay at altitude basal metabolic rate (BMR) (the number of calories required to fuel the body’s expenditure at rest) tests will be carried out at three differing stages of acclimatisation and be compared to the results of the same tests carried out both before and after our sojourn. Of particular interest is the question of whether or not individuals expend more energy whilst at altitude and if so if this is explained by the aforementioned confounding factors or if there is an underlying alteration in biochemical factors.

Integral to the accurate assessment of such parameters is the use of the Cortex MetaMax 3X which has been used throughout the investigation in both the laboratory and altitude based sessions. Pictures below.

As previously stated findings from this study may add to the current understanding of weight loss, energy expenditure, taste sensation and the biochemistry of fuel utilisation at altitude and may lead to the development of a weight loss technique through intermittent hypoxic exposures for an obese population. Furthermore if such an investigation can go a small way in informing the physiology behind weight loss at altitude as intended, there is potential for this information to aid those wishing to maintain weight during trekking in such conditions.

Altitude Illness - Self Report

One of the main issues with travelling to Cusco is that as its at a high altitude (~3400 metres) it can lead to altitude illness. The most common type of altitude illness is Acute Mountain Sickness (AMS) which occurs in 20-70% of people going to high altitude. The symptoms of AMS are a headache as well as one of the following symptoms: nausea, vomiting, lack of appetite, dizziness or lightheadedness, sleeplessness and fatigue. In our group we have been completing an AMS questionnaire on a daily basis to measure the degree to which people have been developing symptoms associated with AMS. I am one of the people that have experienced symptoms suggesting that I have a poorer tolerance to altitude.

AMS. SpO2. Heart Rate
Day 1 morning. 5. 85. 66
Day 1 evening.  8. - -
Day 2 morning. 3. 85. 69
Day 3 morning. 4. 85. 69
Day 4 morning. 0. 94. 63
Day 5 morning. 0. 95. 72
Day 6 morning. 1. 92. 74

On the first full day in Cusco, even though I had a good long sleep the night before as I hadn't slept much on the plane journeys and I was already showing signs of AMS. I had a moderate headache, which is the main symptom of AMS as well as moderate light headedness. I also had an oxygen saturation of 85%, which was low in comparison with the rest of the group. Throughout the day the headache and dizziness became severe and I put an AMS score in the comments section as I felt it had significantly changed from the morning. The headache was very strong and had similar characteristics to a migraine as I struggled to cope with bright lights, therefore I was instructed to take ibuprofen. This did dull the headache down and allowed me to get a good nights sleep. If this had not improved my symptoms or had i felt as bad in the morning I would have been given Acetazolamide.

The onset of the illness usually in the first three days of reaching high altitude and usually lasts the same period. This is certainly the case with me as my questionnaire scores were greater in the first three days of the trip. In this period I consistently had a headache of a mild or moderate intensity as well as other symptoms. My saturation also stayed low at 85% while my resting heart rate remained relatively consistent. I found that the feeling was very similar to a hangover.

Those at greater risk of AMS are those who make a rapid ascent, people who have had a recent cold and retain fluid at altitude or do not urinate excessively at arrival at high altitude. Due to travelling from Eastbourne at sea level to Cusco this would make it a rapid ascent therefore predisposing people to the illness. Also on the first day I drank 4.5 litres of water, a bottle of coke and a cup of tea but only had five urinations. This suggests that I was retaining my fluids as well as not urinating excessively at arrival. Although i would have had a higher than normal sweat rate due to the excessive heat. I also experienced high altitude oedema in my ankles and lower legs which occurs more frequently in those with AMS.

After the first three days, my oxygen saturation significantly improved as well as my results on the questionnaire. This fits in with the idea that the illness occurs in the first days, after this period the results and my general feelings suggest that I have become acclimatised to the low levels of oxygen so that the necessary amounts of oxygen can be transported to the cells.

We haven't had any members of our group suffer with severe AMS, High Altitude Pulmonary Edema or High Altitude Cerebral Edema. This would be unlikely normally, but more so as our group are specifically measuring responses, very weary of symptoms and have been treating any symptoms early and appropriately. As we have gone past the time when you are most likely to have altitude illness hopefully nobody else will suffer with any altitude illness. We are carrying on the questionnaire and physiological measures to identify any problems that may arise. The next danger point is the increase in altitude along the Inca Trail which goes up to ~4200 metres but hopefully everyone will get through unscathed.

James

Day Four - Sacred Valley

So guys... our sixth day in Peru took all 29 of us on the sacred valley tour. With few of us still feeling a tad peaky to say the least we headed up the winding road that exits the back of Cusco past the Jesus Christ statue. Our chatty tour guide informing us all the time of the influx of eucalyptus from Spain in the 1900's, the sprawling topography and various inca traditions that have sprouted from Cusco being the physical and spiritual capital of the Inca people.

Our first fleeting stop saw us pull in at a side stop overlooking a deep valley with towering mountains flanking a tiny market village. After realising why we were struggling with sightseeing thanks to our guide's indecisive left and rights we made the quick hop down the valley and took a break and our first taste of a Peruvian market. As we were soon to find out both Alex and Dom couldn't resist the temptation to buy a useless yet amusing garish balaclava each. This wasn't their last purchase.

We carried along the winding road that at times offered a plummeting shear drop deep into a sprawling valley with the town of Pisac nestling astride the Urubamba, Vilcnota, river. An impromptu stop in another lay-by provided Alex and Dom's second purchase, a bird whistle, that as you can imagine thrilled everyone else on the bus. Our journey took us onto our first Inca experience with a ramble across the precarious Pisaq ruins.

Now chica's and chico's this is where we started to feel that we were being immersed the Inca world. A few of the less fortunate among us held back on the bus with the ill effects of Pooru, Peru's equivalent of the Delhi Belly, still doing its worst. The ruins tour took us on a circular route of a hillside settlement that consisted of both older inca and more recent ruins. This also gave us an insight into the terrain that we'll face a week from today when we set foot at the bottom of the inca trail. Some people were second guessing their fitness and almost everyone was blowing by the time we'd made it back to the bus. It's going to be a hard effort...right?





With a few tired bodies we clambered aboard the bus and made our way to lunch. The journey had an unknown length but luckily the incredible views and sceptical driving style of our bus driver kept us all entertained. At one point while rounding a sharp hairpin bend on loose gravel and with two cars overtaking us, horns blazing, a large lorry rounded the corner. He'd never make it surely... amigos... I assure you, he made it with inches to spare, plenty of room! A gasp and sighs of relief turned to raucous laughter as the pocket size lorry driver with only a handful of teeth beamed a toothless smile through the window not a foot from us.





A bus load of hungry, wearisome UoB staff and students rocked up at the plush looking La Alhambra restaurant that for all intents and purposes seems placed solely for the travelling contingent and seemed totally out of place surrounded by a road strewn with mud brick huts and unfinished buildings (Kane).

The buffet was a miracle for a few broken bodies and with everyone having their fill and a few having more than their fill, naming no names Ollie, we retired to the gardens that provided a welcome break from the monotony of the bus journey. A small group of llama and an alpaca provided entertainment and as you can guess guys some of the students got a little too close to comfort! Kane was once again in his element surrounded by the fruits of nature and bonded immediately with the well groomed alpaca.



A shorter hop on the now more up beat bus delivered us to the Ollantaytambo ruins. Our idiosyncratic tour guide once again showed us the vast doings of the incas almost five an a half thousand years ago. A beautiful amphitheatre of enormous steps rising some one hundered foot plus from the valley floor ascended the mountain before us. There were many a groan at the though of yet another ascent but as the steps fell away behind us and as the guide regaled us with stories of the ancient Inca people hauling huge igneous rock cubes up the unimaginably steep incline we were captivated.

The huge steps provide the Inca's with plentiful farm land that was otherwise unmanageable. We started to realise and respect the knowledge and ingenuity of these ancient people. Their temple made of vast pieces of stone were perfectly placed to worship the movements of the sun and the stars. You know guys this is the most important aspect of Inca life.





With a new understanding of the ancient people and a few bargains found in the market at the foot of the ruins we made our way to our hostel for the night.

So señor a a señoritas we can only finish on the fact that Luke Holland polished off a whole Guinea pig, head and all. Lets hope he doesn't feel the wrath of Pooru tomorrow... thanks guys!

Harry

Day Three - Fat Testing & Ceremony

Oli having his basal metabolic rate measured in Cuzco
using the Metamax 3X 

The day started bright and early with lots of testing as both the hydration and fat metabolism studies were taking place.




















Ben's fat metabolism study required the subjects to lie down for 45mins before a basal metabolic rate test using a Cortex Metamax 3X and a measure of their lipid profile was taken using a Cardiochek.

The study is looking at the effect of an 18 day altitude sojourn on fat metabolism and energy expenditure. Today's collection follows on from the sea level testing prior to travelling to Peru.

Half the fat study cohort resting before their tests - Cosy

After data had been collected and we had eaten another hearty breakfast of rolls and jam with the added option of fruits, yoghurt and sugar puffs, we departed for the third day at the school.  Arriving at the school just after 10am, after buying more local bread on the way. We were a few down on numbers today due to the altitude and a few upset stomachs, but the remaining group of 25 set upon the tasks in hand. Extremely hot, work was tough going, but the group keep motivated extremely well.

A ceremony at lunch with the school children and teacher took place, with the burning of the cocoa leaves we made a wish on when we arrived at the school on the first day. Each child gathered their corresponding student "buddy" and each took a turn to throw some mud onto the burnt out fire! The children said their prayers and thanks, which Arron translated into English for us.
After lunch, some of the group went for a short walk round the lake, admiring the amazing views and scenery.

Arron at the ceremony in the coliseum  

The afternoon work was tough going as temperatures climbed, but the group continued as best they could with weeding the playground and clearing all of the chopped grass and soil. Heavy rain brought an early conclusion to the work, with everyone being extremely tired. The bus journey back was a lot longer than normal as the earlier rain had left the roads flooded.

An early night was had by many, although some ventured to the nearby restaurants for either pizza or chicken and chips (everyone being adventurous!!)

A good but tiring day, with everyone looking forward to tomorrow's Sacred Valley Tour.

Jacob and Rebecca

Day Two - The Walking Tests

First on the agenda was completing another morning of hydration testing, taken place during our first morning of rain. 

Once hydration testing and breakfast was eaten we made our way to the local athletics track to complete our first day of six minute walking tests at altitude. The general consensus was that there was a clear difference between the walk tests completed today and those done in eastbourne. An unexpected experience was sharing the stadium with club cienciano, cuzcos local football team and local press.

Once the walking testing was complete and the data was gathered, we made our way to the school and begin a days work. Yesterday's projects were continued at the same intensity along with new ones. The coliseum has been completely transformed, weeds were removed followed by a new path being built. The medicine garden clearing was completed, and the entry road and path were levelled and improved. The access road work was influenced by a local farmers wife who gave some advice on trench digging.

Proceedings were interrupted by a huge storm that rolled down from the mountains, and littered us with hailstones and rain. Once lightning had ceased work could then proceed. The children's playground was also cleared, meaning the children can now play on equipment they could not before. A day of real hard work was put in by everyone and the school grounds look completely different after only two days.

Projects for tomorrow that have been started include a wall being built to support a path which will allow access to the chicken coup and the agricultural area, projects such as this will have a real long lasting effect on the functionality of the school. The coliseums path is also to be finished and the play area will be cleared further.



Lee, Alex and Dom.

Day One - First visit to the school

We all awoke early this morning from a mixture of jet lag and dehydration, but feeling refreshed from travelling. This morning started with breakfast and hydration testing and we all had lower O2 saturation than in England. Some of us feeling better than others, Harry and Jacob started the day with a run around the nearby mountains, which although they new it would be different to back home, they were shocked to discover how tough it was.

We then drove to the school passing through other local towns with our trip organizer Aaron telling us lots about the sites and cultures. When we arrived we met all the children for the first time, we were greeted with a hug and they all seemed happy to see us. A welcome ceremony took place, where we were paired with the children and tried some of the beans they had been harvesting. This was followed by a sacred tradition where we each made a wish on 3 cocoa leaves, which were then burnt to give thanks to the mother mountains. All of the children we keen to show us around, which ended in a big football match, and pushing them on the swings. After exploring the school grounds, we realized we had quite a lot of work to do over the next week, but we all had lots of ideas and enthusiasm about how we could help. Once we had paused for lunch we got to work clearing the weeds, and became familiar with the equipment we will be working with for the rest of the week, such as pick axes and sickles. 

After only an hour of work we seemed to have accomplished a lot and the grounds visually looked much better! It wasn’t all hard work though as we were kept entertained with Dom managing to catch an escaped chicken after us chasing it around the playground! At around 3pm we got on the bus to come back to the hostel with everyone feeling a little tired again but most have us seem to have coped with the altitude so far.  On the journey back Aaron arranged for us to eat at a local restaurant this evening, we aren’t too sure what to expect but we’ve heard the local delicacy is guinea pig and alpaca steaks!

Alice, Alice and Sophie

The Final Testing Week

Measuring Sophie's metabolic rate
using the Metamax 3X system, Cortex Medical

Final part of sea level testing

With only 5 days to go, all the sea level studies are coming to an end and everyone is getting rather excited, mainly because they can now sleep in past 6am.

FAT STUDY

The main study being carried out this week is the fat metabolism at altitude study, in which we aim to assess whether individuals increase metabolic rate, reduce appetite, suppress taste or exercise more when at altitude. This study considers a range of measures such as basal metabolic rate, daily appetite, taste, leptin changes, body mass and lipid profile markers (free fatty acids, cholesterol, triglycerides) pre, post and throughout the project. For some this was their first taste of having a cannula in their arm (required for multiple venous blood samples) needless to say some didn't take too well to the sensation. Multiple respiratory samples were taken while lying down for 1 hour and then while sitting to ascertain metabolic rates. Measures such as oxygen use, carbon dioxide production and therefore the substrates used for energy production were measured using the Cortex Medical Metamax 3X system.

Dominic doing his heat tolerance test

HEAT STUDY

The final few training sessions are being completed and then everyone will have their final heat tolerance trial. Both participants and experimenters have found this hard work as the monotony of 90mins cycling at 40C with rectal thermistors takes its toll. Please see our previous for more details of this study.

Summer having her SaO2, blood pressure and
body fluid compartment volumes measured

HYDRATION STUDY

Participants completed their second hydration measurement session for their double baseline over this week. This study requires the measurement of body fluid compartments and hydration throughout the project. Testing for this is a lot more relaxing, with subjects providing a urine sample, body mass and then laying for a long period before multi-frequency bioelectrical impedance analysis, SaO2, blood pressure and heart rate was taken. 

The lightweight Seca scales and the Nonin Plus pulse oximeters that will be travelling to Peru and up to Machu Picchu with us were kindly donated by Cranlea.

Getting Warmer

Things are hotting up...

So the cycling continues. The mid Heat Tolerance Tests are starting to be completed as people finish their 5th heat acclimation session. Without measuring physiological values, it is clear to see people are already finding a noticeable improvement in their tolerance to the training in the heat. Yet it is still seems to be pretty hard work for those doing the heat based trials as you can see from our video.

Testing Week Two

Heat Acclimation Overload

Another week of testing with the start of the heat acclimation process for one third of the students on the project. The heat acclimation training requires 10 days of 90mins cycling at 50%VO2max in 40 degrees Celsius. Measures of heart rate, rating of perceived exertion, thermal sensation, core temperature and physiological strain are taken every 5th minute for all participants.

The other two thirds of the group are either completing a normothermic training for the same duration and intensity, or no training at all. The students in the control doing no training at all are acting as the experimenters and busy collecting all the data from the 16 exercising participants.

Needless to say, the heat acclimation hasn't been easy, but the 8 students completing the training have worked hard so far, especially considering this has had to be done around their normal students and the considerable amount of work that is due in soon or immediately after Peru.

In the week prior, participants had completed VO2max tests and heat tolerance tests in which they run until exhaustion in the 40C environment. All participants will complete these tests again after 5 and 10 training sessions.

Participants are also required to give venous blood samples at the same time points. This is to measure various blood markers including heat shock protein 72, a protein chaperone known to be up-regulated when the body is subjected to sufficient environmental and physical strain. It is suggested that by up-regulating HSP72 an individual may improve their tolerance to environmental extremes such as heat and altitude.

Oli Gibson, who is leading this research project, is now looking rather more stressed than normal, as the snow day and closure of the University has caused all sorts of problems with rearranging of testing, lectures and bookings for the chamber. Fortunately it all seems to be going well, follow our twitter page to follow how it goes.

Testing Week One

Labs looking relatively clear before the enslaught

Week One - TICK

So at the end of week one of four, we have been successful in completing all 29 VO2max tests, 29 Heat Tolerance Tests, 174 normoxic and hypoxic walking tests and 29 hydration tests. Not bad at all.

Alice M, James and Ben D completing an outdoor walking test

Lee doing his hypoxic walking test

6MWTs

Of all the tests the 6min walking test has been the most surprising in that it is deceptively painful on the lower leg muscles, yet it also very repeatable. Time and statistical analysis will tell but the immediate response is that many people across hypoxia, normoxia and outdoor got very similar and representative distance and physiological results. 

Ben P completing his first heat tolerance test

Dominic looking he is enjoying the 40C

Tess completing her VO2max test using the Cortex Medical Metalyser

VO2max

Oli has been busy conducting all 29 VO2max trials on the cycle ergometers and using the Cortex Medical Metalyser, which has worked really well and calibrated first time every time, especially considering the number of tests completed on the one machine in one week. 

Ben's study on fat metabolism at altitude, which starts in two weeks time, will be using the Cortex Medical Metamax 3X for  

Although it has been busy and a little hectic at times, I believe everyone has enjoyed it. From a staff perspective it seems like it has brought all the students and staff together in the realisation that we are all in this together. Of course this research is all in addition to normal workloads of both the staff and students so working round lectures and meetings has been interesting at times.

For updates on the testing and some excellent pictures of very sweaty individuals please follow our Twitter page @UOB_PERU2013