Techkewl vest arrived today, made it my profile pic, haha.
Great picture of you and your cooling vest. Thanks for sharing it! I look forward to getting my own when it becomes necessary here in Pennsylvania. It looks like a good fit.
How big are you, and what size did you get? The M/L version I presume?
How long does the cooling effect last before a recharge is required and how long does it take to recharge the inserts in the freezer?
I think they use some type of paraffin for the PCM, but I'm wondering if coconut oil would do the job?
I suspect coconut oil (with a melting point
of 77F) would work, perhaps mixed with olive (21F) or peanut oil (37F) to bring down the melting point, and the price!
Here is what I might do, if I decide I don't want to spring for a second set of OEM inserts from Techkewl
, or from one of the other makers of inserts linked to above:
- Put the right volume of a mixture of oils into ziplock sandwich bags.
- Put the sandwich bags flat in the freezer to get them to solidify into the right shape.
- Once solidified, remove the slugs of solid oil from the sandwich bags and vacuum seal them into durable freezer storage bags of the right size.
The freezer bags that come with vacuum sealer machines are quite rugged, and the vacuum seal is permanent (unlike sandwich bags), so I wouldn't worry (as much) about them leaking, especially after many freeze/thaw cycles.
I actually like cooler temps in general, I find it pleasant.
Interestingly, I too am experiencing a growing preference for cold conditions. Yesterday I went on my weekly excursion from my house (to grocery shop and get the tube replaced on my stationary bike). It was a unseasonably mild day in PA, about 55F. Driving along in the enclosed car seemed too warm (even with the heat off) so I opened the windows while I drove. It felt very refreshing and invigorating. I suspect it may be a sign of cold adaptation via the synthesis of brown (or beige) adipose tissue via the combination of cold exposure  and exercise .
I'm no Wim Hof (aka the Iceman) yet, but I may be getting there.
 Diabetes. 2014 Nov;63(11):3686-98. doi: 10.2337/db14-0513. Epub 2014 Jun 22.
Temperature-acclimated brown adipose tissue modulates insulin sensitivity in
Lee P(1), Smith S(1), Linderman J(1), Courville AB(2), Brychta RJ(1), Dieckmann
W(3), Werner CD(1), Chen KY(1), Celi FS(4).
In rodents, brown adipose tissue (BAT) regulates cold- and diet-induced
thermogenesis (CIT; DIT). Whether BAT recruitment is reversible and how it
impacts on energy metabolism have not been investigated in humans. We examined
the effects of temperature acclimation on BAT, energy balance, and substrate
metabolism in a prospective crossover study of 4-month duration, consisting of
four consecutive blocks of 1-month overnight temperature acclimation (24 °C
[month 1] → 19 °C [month 2] → 24 °C [month 3] → 27 °C [month 4]) of five healthy
men in a temperature-controlled research facility. Sequential monthly acclimation
modulated BAT reversibly, boosting and suppressing its abundance and activity in
mild cold and warm conditions (P < 0.05), respectively, independent of seasonal
fluctuations (P < 0.01). BAT acclimation did not alter CIT but was accompanied by
DIT (P < 0.05) and postprandial insulin sensitivity enhancement (P < 0.05),
evident only after cold acclimation. Circulating and adipose tissue, but not
skeletal muscle, expression levels of leptin and adiponectin displayed reciprocal
changes concordant with cold-acclimated insulin sensitization. These results
suggest regulatory links between BAT thermal plasticity and glucose metabolism in
humans, opening avenues to harnessing BAT for metabolic benefits.
 Diabetes. 2015 Jul;64(7):2361-8. doi: 10.2337/db15-0227. Epub 2015 Jun 7.
Exercise Effects on White Adipose Tissue: Beiging and Metabolic Adaptations.
Stanford KI(1), Middelbeek RJ(2), Goodyear LJ(3).
(1)Section on Integrative Physiology and Metabolism, Joslin Diabetes Center,
Boston, MA Department of Medicine, Brigham and Women's Hospital, Harvard Medical
School, Boston, MA. (2)Section on Integrative Physiology and Metabolism, Joslin
Diabetes Center, Boston, MA Department of Medicine, Brigham and Women's Hospital,
Harvard Medical School, Boston, MA Division of Endocrinology, Diabetes and
Metabolism, Beth Israel Deaconess Medical Center, Boston, MA. (3)Section on
Integrative Physiology and Metabolism, Joslin Diabetes Center, Boston, MA
Department of Medicine, Brigham and Women's Hospital, Harvard Medical School,
Boston, MA email@example.com.
Diabetes. 2015 Sep;64(9):3334.
Regular physical activity and exercise training have long been known to cause
adaptations to white adipose tissue (WAT), including decreases in cell size and
lipid content and increases in mitochondrial proteins. In this article, we
discuss recent studies that have investigated the effects of exercise training on
mitochondrial function, the "beiging" of WAT, regulation of adipokines, metabolic
effects of trained adipose tissue on systemic metabolism, and depot-specific
responses to exercise training. The major WAT depots in the body are found in the
visceral cavity (vWAT) and subcutaneously (scWAT). In rodent models, exercise
training increases mitochondrial biogenesis and activity in both these adipose
tissue depots. Exercise training also increases expression of the brown adipocyte
marker uncoupling protein 1 (UCP1) in both adipose tissue depots, although these
effects are much more pronounced in scWAT. Consistent with the increase in UCP1,
exercise training increases the presence of brown-like adipocytes in scWAT, also
known as browning or beiging. Training results in changes in the gene expression
of thousands of scWAT genes and an altered adipokine profile in both scWAT and
vWAT. Transplantation of trained scWAT in sedentary recipient mice results in
striking improvements in skeletal muscle glucose uptake and whole-body metabolic
homeostasis. Human and rodent exercise studies have indicated that exercise
training can alter circulating adipokine concentration as well as adipokine
expression in adipose tissue. Thus, the profound changes to WAT in response to
exercise training may be part of the mechanism by which exercise improves
whole-body metabolic health.
© 2015 by the American Diabetes Association. Readers may use this article as long
as the work is properly cited, the use is educational and not for profit, and the
work is not altered.
PMCID: PMC4477356 [Available on 2016-07-01]
 Ann Nutr Metab. 2015;67(1):21-32. doi: 10.1159/000437173. Epub 2015 Jul 25.
Role of Exercise in the Activation of Brown Adipose Tissue.
Sanchez-Delgado G(1), Martinez-Tellez B, Olza J, Aguilera CM, Gil Á, Ruiz JR.
(1)PROFITH 'PROmoting FITness and Health Through Physical Activity' Research
Group, Department of Physical Education and Sport, Faculty of Sport Sciences,
University of Granada, Granada, Spain.
BACKGROUND: The energy-burning capacity of brown adipose tissue (BAT) makes it an
attractive target for use in anti-obesity therapies. Moreover, due to its ability
to oxidize glucose and lipids, BAT activation has been considered a potential
therapy to combat type 2 diabetes and atherogenesis.
SUMMARY: BAT is mainly regulated by the sympathetic nervous system (SNS); yet,
recent findings have shown a group of novel activators that act independently of
the stimulation of the SNS such as cardiac natriuretic peptides, irisin,
interleukin-6, β-aminoisobutyric acid and fibroblast growth factor 21 that could
influence BAT metabolism. Several strategies are being examined to activate and
recruit BAT with no side effects. In this review, we postulate that exercise
might activate and recruit human BAT through the activation of SNS, heart and
KEY MESSAGES: Epidemiological and well-designed exercise-based randomized
controlled studies are needed to clarify if exercise is able to activate BAT in
© 2015 S. Karger AG, Basel.
There will never be peace in the world while there are animals in our bellies.