Homemade Electrolyte Drink

After last weeks bad experience with salt loss, I decided to make my own low-calorie, higher-salt electrolyte drinks and try them out on on this Sunday's hiking.

I got some ideas from this link.  The key discovery is coconut water as a base as it has high salt and potassium (although 200cal/litre).   I didn't add much sugar as I wanted to keep the calorie level down.

For each drink I tried to get the salt content similar to sweat at 900mg/l, but I overshot slightly.  Also after I'd finished I decided 700mg would have been safer, so I packed some plain water and Pocari Sweat to lower the average salt concentration.

Before

The line-up for Sunday (left to right):  

Coconut water.  (200cal/l)

Gingered water with lemon juice.  

Watermelon and coconut water  (150 cal/l)

Pureed strawberry and coconut water 

Pocari Sweat (240 cal/l)

Plain water

After

Conclusions from the field test:  

1. I had no issues with cramp etc.  Despite hiking for 9 hours and sweating 7+ liters.   
2. Water-mellon and Coconut Water was the most refreshing.
3. Coconut Water was also nice and very easy to make (just top-up salt 250mg/l)
4. The 1g/l salt content was a little too high.  Packing some lower-salt drinks and plain water was a good idea.

Wilson Trail Stage 3

Since it was such a lovely day on Saturday I made an impromptu decision to go hiking right after Tai Chi.  

I chose stage 3 of the Wilson Trail which starts at the eastern entrance of Hong Kong harbour, just 2 stops on the MTR from my class at North Point.   I skipped the first 1km and joined the trail at Yau Tong MTR station.  I probably lost most of that 1km trying to exit from the gigantic MTR mall,  but I was able to buy a water, food, sunscreen, insect repellant, a hat and hiking shorts.

Hong Kong harbor from Yau Tong.   The hills commanding the entrance to the harbor have some old military forts.  I skipped them because I mistakenly thought I didn't had enough time.

The path goes alongside the Chinese Cemetary, and along the ridges above beside the path was a series of small unofficial looking shrines overlooking the harbor.

View from Devils Peak (202m).  Looking west from one of the shrines    

The shrine that enjoys the view in the photo above

I continued up the ridge to Black Hill (304m) which gives nice views of Hong Kong Karbour, its eastern approaches, and Clearwater Bay.

Also Tai Lo Shan (Tates Cairn) and Ma On Shan to the far north. (My target for Sunday)

Panorama:  view from Black Hill

After Black Hill the Wilson Trail path left the ridge and descended through forest to a series villages .

Along the way I passed this quirky but spooky shrine with a host of painted sculptures of people and animals.

 They reminded me of Latin American 'Day of the Dead' decorations.  

There was even one looking like a mad Gweilo pig playing the shakuhachi

I finished Section 3 at Clearwater Bay Road at 4pm having done 8.3km in under 2.5 hours.

Wilson Trail sections 8.5 to 10.5: Cloudy Hill & Pat Sing Leng

With Hannah and Rika still in Japan, I wanted to make the most of my freedom and hike some of the longer tougher routes that I normally wouldn't be able to do.   I particularly wanted to do the Wilson Trail section 9 along Pat Sing Leng, the high ridge on the north side of Tolo Harbour.

I started late at 9am joining the Wilson Trail midway along section 8 at Tai Wo.   The forecast was for hot weather 30-32 degrees and 75-95% humidity.  I brought plenty of liquids :  5 liters of Pocari Sweat sports drink and 3 liters of frozen water, making my pack about 10kg.

Section '8.5' (map) climbs north from Tai Wo and finishes 3.5km later on the top of Cloudy Hill (440m).   The photo above shows Cloudy Hill from Tai Wo.

And the photo below shows Tai Wo from Cloudy Hill after 1 hour of tough climbing.  Tai Po new town is on the left and Lead Mine Pass in the haze of the middle horizon.  It was already 32C degrees and high humidity (80-90%)

Tolo Harbour and east Tai Po from Cloudy Hill.

Now officially on section 8 (map), the Wilson Trail loses almost all the hard-won height as it descends Cloudy Hill through the forest to Hok Tau Reserviour.   The sign-posting wasn't great and I made an unintended detour to Lau Shen Reserviour which added 2.4km and 100m climb to the route.  But I reached Hok Tau at 12 noon ready to begin the real hike.

Pat Sing Leng, the 'Ridge of Eight Immortals' (wiki link) consists of 8 peaks 510m-590m high, each named after one of 8 Immortals in Chinese mythology.  The chinese name uses one of my favorite characters, 仙, which shows one person (left) and a mountain (right).  The Japanese would read it as 'sen' or 'hermit', and when I have shakuhachi lessons I must make a pilgrimage to my teacher's house at 'Sengawa' or 'Hermit River'.

This is Pat Sing Leng range from above Hok Tau Reservoir.   The trail ascends 500m from the valley floor straight up the ridge and then up the valley on the left.  One of the reasons the peak is considered  the most difficult in Hong Kong (afcd link).

In the 32 degree heat and high humidity, the climb was brutal, despite frequent stops to drink 'Pocari Sweat'.   However the frozen water bottles in my pack were still mainly frozen which kept the other bottles nicely chilled.   But I was too tired to take photos.

When I was almost at the summit there was a loud thunder-storm just above.   I waited it out with a party of locals in a sheltered part of the track, thinking I would have to give-up and go back down for safety.  But after 30min the thunder stopped and the group resumed their ascent.  So I decided to follow them up.  

Despite the thunder we emerged on the glorious open plateau behind the peak in sunshine.  I could now see the north across the massif to Starling Inlet (below).  This would be a truly magnificent view on a clear day.  But given the heat, I was rather glad of the cloud-cover, since my legs cramped up badly for a while.  

The next section was a wonderful hike east along the 8 peaks, with the dramatic drop to the right (south) and spectacular views across Tolo Harbour.   The sun was now at my back and clouds and a lovely breeze took the edge off the heat.

The photo below shows the view south-sest toward Tai Po.  The white figure far right is the 76m Guan Yin (Goddess of Mercy) statue at Tze Shan monastery which will be the world's tallest bronze Guan Yin when completed this year (link).

And looking south-east towards Ma On Shan with the Plover Cove dam on the left.

I progressed along the long ridge and ran into another reason this hike is regarded as challenging - the descents and ascent between each 'immortal'.   Each one quite reasonable on its own, but collectively they are tough.  The path was extremely hot whenever the afternoon sunshine broke through the clouds.  I finished off the last of my 5l of Pocari Sweat around 3pm.  

This is the view looking east to from the 2nd last immortal (Sheung Tsz Fung, 510m) the last immortal (Hsien Ku Fung, 514m), with a group of locals on the summit and Plover Cove beyond.

The photo below shows the view west from Hsien Ku Fung along the Pat Sing Leng ridge to Sheung Tsz Fung and Sheung Tsz Fung (591m).   I had a very pleasant break on the summit for about 40min stretching my tired limbs, sipping from my 3l reserve-supply of chilled water, and chatting to other hikers.   

One madman jogged up the ridge around 4:30pm and then immediately set off back west.   Another madman got out a rope and set-off down the sheer south-east cliff towards Plover Cove.   And when the last hiker had set-off down the path, a mad gweilo furtively got out his shakuhachi and played 'Kurokami' a couple of times to the immortals.   

Around 5pm I started the descent, north down section 10 of the Wilson trail to join the Pat Sing Leng Nature Trail Id hiked with Hannah in July.  The 500m drop was much easier than I'd expected, and I made fast progress down nicely spaced steps towards Bride's Pool enjoying the shade and a nice breeze.   I felt really good and gave some of my last water to a couple of lost-looking teenagers, and congratulated myself on how well I'd planned my provisioning.  

I finished the trail at 6pm at Brides Pool having walked 19.7km with around 1,300m vertical climb in 8 hours of actual hiking.   I'd consumed 5 liters of sports drink and 1.5 liters of water.

But as soon as I reached the bus stop things began to go wrong.  Very wrong.   I began to feel unsteady and spaced-out and my hands started tingling.  I had to hold on hard to support myself in the bus to Tai Po Station, and once we arrived I could barely shuffle through the station to the train.  I felt nauseous and wanted to cry for some reason but I was too tired.   I felt so ill that I almost took a taxi straight to the hospital, but that seemed too much work so I shuffled home.

I weighed-in at 88kg, down 2kg since setting out, despite consuming 6.5l of liquids (and not urinating all day).  Implying I had sweated 8.5 liters!    It was obvious that the problem wasn't so much fluid loss so much as  a drop in the salt level in my blood, since the sports drink and water contained less sodium than I was sweating out.   Sweat contains roughly 920mg sodium per liter while the 'Pocari Sweat' contains 490mg and water nothing.  So I'd lost roughly 8.5g of sodium and replaced 2.5g giving a shortfall of 6g.  This seemed to be enough to lower my blood my sodium levels to problematic levels.  

One problem with low blood sodium is that it is dangerous to correct too fast (danger of water retention in the cells and swelling in the brain).   So I had a rather unpleasant evening feeling sick and drinking another 3l of Pocari Sweat to make-up the fluid shortfall.  I didn't sleep well and felt so rough on Monday morning I almost called-in sick.    Another disappointment was that the 8 liters of Pocari Sweat at 260cal/l was a total of 2,080 calories, which offset a lot of the 'fat burning' benefit of the hike.

I've since found a good article on salt loss through exercise (link, 'Case 4' best matches my experience).  However doing the numbers, I think that with my mild dehydration I should still have been alright.  Unless I'd already started the day with low blood-sodium, which is quite possible since I also hiked 5 hrs the previous day and rehydrated / pre-hydrated with water.

So what are the takeaway from this experience?  

1.  In the heat, long hikes (8+ hr) are much trickier than short hikes, and require consideration of electrolyte balance as well as hydration.

2.  Make sure to start the hike with a good hydration and electrolyte balance.  

3.  Take 'electrolyte' drinks rather than pure water.    

And I initially thought 'Take drinks with salt content as high as your sweat (900mg /l)'.  

But it seems this is also potentially dangerous.  As the article shows (case 5), if for some reason you your blood-sodium concentration rises too high you will feel thirsty but you won't be able to lower it by drinking such a salty drink, giving a danger of over drinking.   Which is probably why Pocari 'Sweat' is only 490mg.  So...

4.  Take 'moderately salty' drinks (c. 700mg/l)'  and some lower-salt drinks in case you get thirsty...

5.  Take some salty foods to top-up sodium if you get symptoms like cramps, as well as foods high in potassium like bananas. 

6.   If you want to burn fat, make your own lower-calorie electrolyte drink.  (Of which more anon).