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  3. The trail conditions at Rocky Hill are pretty sweet. Just a few days past Hero Dirt from the recent rain. With a three-day weekend upon us, RHR temperatures will be prime if you can get on the trail in the morning. Though I've seen riders coming out in the hot part of the day recently too. With the trees shading so much of the trail it sure takes the edge off riding in direct sun. More good news! There is a new brewery in town. Smithville Brewing Company They are currently offering taps of other Texas craft brewers while ramping their production. There is a food trailer (Bay Bay'z Seafood 👍) there through this weekend. SBC are located on the right as you drive from RHR into Smithville, a little ways past the Airport entrance. Happy Hour is 4-6 with $2 off pints (bought an Oatmeal Stout and an Eastciders for less than $6). They have open-air seating inside and a Biergarten outside with picnic tables and shade cloth overhead. I'm thinking this is going to be a great hang-out for post-ride and post-trail-work recovery therapy. Come get some!
  4. ATXZJ

    Random Dogs

    Tater tots are a helluva drug🤣
  5. Yesterday
  6. Put signs out today for the Rest Stops Here's some photos The Fine Print
  7. Thumper is more of a sous vide ride rather than an air fryer ride.
  8. Thumper is hands down the hottest trail in Austin during the brutal heat, IMO. I brought some race fit buddies back there yrs ago in August and we seriously couldnt get out fast enough. It's like a sauna down in that valley with the humidity and zero air flow. We made it to Bull Creek and had to cool off in the skank water before climbing out. We all rated that as, 'the bad decision dirt ride"
  9. I always felt CP or Thumper would cook you faster, but maybe something with more air? How is Lakeway at worst peak heat?
  10. I got a long sleeve Swiftland Running T Shirt from REI for sun protection. The wispy fabric is astoundingly light and incredibly ventilated, so I got another one. REI Co-op Swiftland Long-Sleeve Running T-Shirt - Men's
  11. Last week
  12. Yep, it's all about the airflow. When you stop for a light, it feels horrible, and the sweat starts accumulating, but the payoff is when you start moving again. It feels like AC. On days when evap is not great, I also take an insulated water bottle with lots of ice and splash a little bit in the crooks of my arms and on my head if I hit a red light.
  13. now the question is: what trail should we just nickname "Air Fryer" now? I don't think I am capable of creating enough "air flow" to make a different. maybe that's why road rides feel slightly less horrible, especially if you avoid the hilly routes that involve slowly grinding up the climbs.
  14. This just reminded me of one of my hottest/awful feeling rides ever. It was RHR 24 hour race, usually around Halloween (one week before or after, same as the EB). It was crazy hot at hour 6 (6pm). It was also fairly dry and the single bottle of hydration mix + extra water bottle per lap (~50-70min laps) was not enough. I went into debt. I decided to do a long stop around 6pm, rehydrate, cool down, and avoid the hottest part of the day (a section in the first part of the course...the long winding climb was the worst!) Even though I lost a lap to some people, it was the best strategy. I was able to finish the race while others just went too deep and dropped out. I wasn't scared that time...but I was at the BCGB one time. Ran out of water, couldn't find my way to the tennis courts, not feeling great. I thought of Bear Gryll's advice (head downhill toward the water) and sat in a nasty pool of green water which cooled me down significantly and I was able to ride the main trail to Zylker and water.
  15. Thanks. I was familiar with wet bulb temp and heat index as the "feels like", but I was definitely not as familiar with what it means as far as evaporation. I had to read up on the details, and found this excellent summary which includes solar irradiation estimate. https://www.weather.gov/ama/heatindex BTW, increased convection helps with evaporation, but evaporation is different from pure convection. I would still like to see a separate chart that takes airflow into account. All the heat index stuff basically assumes you're in the shade and not moving. Looking at this from the engineering side, we always have to take into account: airflow, ambient temp, humidity, and altitude. All those affect conduction, convection, and evaporation. For sure when I ride in the heat, I hate going up a slow hill which usually also means head wind is getting blocked by the hill, or I have a tail wind (the worst). This is why I stick to the flatlands. It feels way different even in high heat index conditions.
  16. The "Heat Index" provided by weather sources is based upon calculating for evaporation based upon current temp and humidity. This is what it feels like outside to one of us hairless monkeys. Currently I see 87F air temp, 95F heat index, and 60% humidity. Normal skin temp range is 91 to 98 degrees. If the heat index (sweat effectiveness) is higher than current skin temp the heat will move from the air to the skin and increase core temperature. Add to this the heat the body is producing and is unable to shed and the rate of core temp increase steepens. This will be true with heat transfer via conduction, convection, and radiation. So, sweat evaporating from the skin is a convection path, the sweat-soaked shirt unable to evaporate fast enough and holding heat (water is efficient at holding heat) is a conduction path, and the sun shining on bare skin is a radiation path for heat. Let's say skin temp is 95F and the heat index is 97F. A 2 degree spread probably isn't enough to remove all the heat being produced by a rider. Add to this heat gain from sunshine, and the stored heat in soaked clothing and it is unlikely there is any other outcome than for the core to increase in temperature.
  17. Heat input + Heat generated = Heat output (evaporation + conduction/convection) to maintain temperature. Neglecting heat input and conduction/convection.... If you're doing nothing, just sitting around and are an average male, you'll be burning 2000-2500kcal a day. Assuming the latter, that means 104kcal per hour. At 540cal/g, you'd need to vaporize 192g of water (192mL) to maintain temp. If you are riding tempo, you're likely going to be burning 600-800kcal/hr. Assuming the latter, that means you need to evaporate 1.48 liters of water per hour to not overheat. If the humidity doesn't allow you to evaporate that much water, you will either overheat or (more likely) your body will force you to slow down. I need to research convection cooling. I am assuming it's very small compared to evap, but I'd like to find out for sure.
  18. FWIW, this matches a study I read ten or more years ago regarding the relationship of high ambient temp and core temp. It was part of an article to warn motorcyclists of the dangers of overheating in the Summer. Back then the point two university studies had determined was 93F, a few degrees higher than what this study determined. It went on to say how once air temperature reaches a certain point the heat becomes less effectively removed from the body even if the sweat is evaporating. The greater the air temp is higher than the skin temp, the more heat will transfer from the air to the body instead of cooling it. This results in heat building up in the core over time (and exertion) and increases risks for a number of health issues. Essentially, the convection is occurring, only it is in the other direction, heating the cooler surface, the skin/body. I think this is also how an Air Fryer works. 😁
  19. I was getting dressed to ride yesterday evening and checked the weather on my phone. It said the air quality was crappy and I’ve been having a lot of headaches lately that I thought were caused by heat but may be allergies, or dust, or a combination of all three. So instead of riding I took the dog to the Personal Trail Network for a hike and some trail work. He was all about it.
  20. There's no link to the actual paper, and what is written there has so many holes. A couple of questions: 1) How many watts cycling or walking? That matters. (one reason I don't go to the BCGB or Thumper this time of year). 2) Airflow. Was there any? They could have made it educational by comparing heat of vaporization (540 cal / g at 98°F) vs convection. Even at 100% humidity with no sweat evaporating, you will get some convection cooling (probably an order of magnitude lower than vaporization). In the end, I'm not even sure why they performed this experiment. You can calculate this easily. With no evaporation, this boils down to what thermal engineers do all day long every work day of the week.
  21. in case it was not plain enough to me that heat + humidity was a bad combination: https://www.psu.edu/news/research/story/humans-cant-endure-temperatures-and-humidities-high-previously-thought/ it gets worse with age.
  22. Rode the new trails about 2 weeks ago. Lots of fun, a wee bit more climbing then I was used to RHR. That comes from using more of the front part of the ranch and several switchbacks. The newer stuff in the back now, reminds me a lot of riding at Warda(BCR), which is a lot of fun. If anything right now, the trails needs lots of wheels down on them to get them burned in. I was able to navigate the new trails without a trail map, so that is a plus also.
  23. Gave blood about 4 weeks ago. For the first 2-3 weeks I went from averaging 11-12 MPH on urban rides to 10-11MPH urban and struggled on the trails. They said it could be 4 weeks before my oxygen was 100% back to normal. Got on the bike yesterday after 10+ days out of town and averaged ~11.5MPH. Very interested to see how I do on the trails this weekend. Clearly there was an impact.
  24. 70° and 53% currently. Y'all better be hittin the trails this morning.
  25. Decided to take advantage of this cold snap today. Did some fine tuning on the new climb on Black Trac that should smooth it out a bit. I then mosied over to a section of Karaway across from Freeride 512 and added a new section to the trail that takes it over a few more of the dirt piles there. After all that I got to feeling about done for the day, so I downed ~48 oz. of water, followed closely by a Shiner Ruby Red. With the tank topped off it was time to get back in the AC for the rest of the day.
  26. Post-Rain Trail Work at Walnut Creek Metro Park, Tuesday June 28. 5:15pm. Meeting at main pool lot and going to #405 location (south of main creek crossing). Wear pants (poison ivy possible) and bring your own gloves (although we'll have some to share); we are providing tools. The Austin Ridge Riders is YOUR local not-for-profit Mountain Bike Club. ARR builds and maintains the trails we all enjoy. The vision for Walnut trail work is a combination of routine maintenance stuff (lopping face slappers, fixing erosion/drainage issues, etc.) as well as ADDING FLOW & FUN (berms, rollers, log features) while continuing to recognize the trails' multi-use status (hikers, runners, dogs, etc.). If you are not yet a member of ARR, PLEASE CONSIDER SIGNING UP TODAY on http://www.austinridgeriders.com Also, please click here to fill out an online waiver: https://fs27.formsite.com/eINPMl/0xpgcz4ejt/index.html
  27. That age old question rears its head once again ... "is Walnut dry?"
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