Autumn Bathing in River Rhine, 8th of April 2017 - Part I
The system of autumn bathing explained by it's inventor - Matthias Draeger, chairman of the German Institute for Hygiene.

YouTube, Clip of 34 Minutes:

The record was taken on 8th of April 2017.
Water temperature round about 14° C - this is quite warm for this time of the year, due to a warm March.

This 2017 season started quite interesting for me, since I could not go bathing/ swimming until mid of November 2016, due to several angina infections I got via Kindergarten from one of my children.
Usually bathing during all seasons of the year, at least in the years 2014, 2015 and 2016 (until Nov.) I was kind of "off" from the training.
I tried to go bathing with a water tempearture of 8° C in March, but it was too cold for me, I felt not confortable, so just took a both in the sun (with some water spread over my body in order to adapt).

30th of March was the first time I could kind of re-enter my system, staying in the Rhine for about 18 minutes, at 12° C., and feeling comfortable all time.
I have been in the water since then several times (see above),
with the following impression:

- entering the water is not a big issue, as you can see
- staying in the water for the first minutes gives you the feeling you are in kind of "fresh" water, but it is really o.k., especially with some good sun to shine on you
- after some 6 to 8 minutes the feeling of "fresh water" dissappears, and you are really "in" the water, you even feel the "warmth" of the water, it is just o.k., same as you felt it some years ago when you went bathing and swmming in the sea with a water temperature of 20° C.

Being a trained kind of "autum bather" you can then stay in the water for some 20 minutes in total - if you move well, you can make it even longer, some 30 or even 40 minutes all together (as for instance in the 14th of November 2014 videos).

For people with a kind of "strong constitution":
To my understanding there is no better way to get back to your original constitution, to your original shape of your body as with the system of "autum bathing".
It seems to me there is no other sport which deprives you of so many calories/ minute as the bathing in fresh water, especially when prolonged for some 20 minutes or so, and repeated at least 2 times a week.
Bathing in the wonderful sun, in the fresh air, gives an additional effect, a very calm stimulus.
In terms of physiology, with the system of autum bathing your body is stimulated to produce/ transform some n e w b r o w n fat tissue. This brrown fat tissues is present to a high degree at infants, then more or less fades away when we grow up.
But, when stimulated, the organism begins to build new cells of brown fat, which supply the body with the warmth needed to keep ut it's core temperature.
This adaption/ conversion takes about some two to three month, not more.
I can confirm this from own experience: I started to swim in the late seasons of the year in 2014, and started not sooner than August 2014. In November 2014 you can see me swimming at the very same place in the River Rhein for some 40 Minutes, and staying in good mood:

14th of November 2014, bathing in Rhine for some 40 minutes, just the very year I discoverd the system of "autum bathing":

Part I:

Part II:

Part III:



Micrograph of a hibernoma, a benign tumour thought to arise from brown fat (haematoxylin and eosin stain).
It was believed that after infants grow up, most of the mitochondria (which are responsible for the brown color) in brown adipose tissue disappear, and the tissue becomes similar in function and appearance to white fat. In rare cases, brown fat continues to grow, rather than involuting; this leads to a tumour known as a hibernoma. More recent research has shown that brown fat is related not to white fat, but to skeletal muscle.[18][19][20]

Studies using positron emission tomography scanning of adult humans have shown that BAT is still present in most adults in the upper chest and neck (especially paravertebrally). The remaining deposits become more visible (increasing tracer uptake, that is, more metabolically active) with cold exposure, and less visible if an adrenergic beta blocker is given before the scan. These discoveries could lead to new methods of weight loss, since brown fat takes calories from normal fat and burns it. Scientists have been able to stimulate brown fat growth in mice.[21][22][23][24] One study of APOE knock out mice showed cold exposure could promote atherosclerotic plaque growth and instability[25] when study mice were subjected to sustained low temperatures of 4 °C for 8 weeks, which may cause a stress condition that shows rapid forced change rather than a safe acclimatisation that can be used to understand the potential in adult humans during modest reductions of ambient temperature by just 5 to 10 °C.
Furthermore, several newer studies have documented the substantial benefits of cold exposure in multiple species including humans, for example researchers concluded that "activation of BAT is a powerful therapeutic avenue to ameliorate hyperlipidaemia and protect from atherosclerosis"[26] and that brown fat activation reduces plasma triglyceride and cholesterol levels and attenuates diet-induced atherosclerosis development.[27]

Long term studies of adult humans are needed to establish a balance of benefit and risk, in combination with historical research of living conditions of recent human generations prior to the current increase of poor health related to excessive accumulation of white fat. Pharmacological approaches using ß3-adrenoceptor agonists have been shown to enhance glucose metabolic activity of brown adipose tissue in rodents.[28][29][30]

Additionally research has shown:

BAT activation improves glucose homeostasis[31] and insulin sensitivity in humans[32] suggesting that anyone with impaired insulin function might benefit from BAT activation, however there is broader application given research showing even mildly elevated blood glucose in healthy non-diabetic humans is associated with damage over time of many organs such as eyes, tendons, endothelial/cardiovascular system and brain,[33][34][35] and results in higher levels of damaging advanced glycation end products.
BAT activation may play an important role in bone health and bone density.[36][37]
BAT activation though cold exposure increases adiponectin levels, just two hours of cold exposure resulted in a 70% increase in circulating adiponectin in adult men.[38] Centenarians (both men and women) and their offspring have been found to have genetics that boost adiponectin, and they have higher circulating adiponectin, suggesting a link between longevity and adiponectin production[39] In addition, high concentrations of plasma adiponectin in centenarians was associated with favorable metabolic indicators, and with lower levels of C-reactive protein and E-selectin.[40]
Fibroblast Growth Factor 21 Production (FGF-21) has been documented as a pathway to longevity.[41] BAT activation though cold exposure up-regulates circulating fibroblast growth factor 21 (FGF21) in humans by 37%.[42] FGF21 improves insulin sensitivity and glucose metabolism[43] which may partially explain its longevity promoting benefits.
Cold exposure increases circulating irisin.[42] Irisin improves insulin sensitivity, increases bone quality and quantity, is involved in the building of lean muscle mass, and helps reduce obesity by converting white fat to brown fat,[44] providing many of the same benefits of exercise.[45] Healthy centenarians are characterized by increased serum irisin levels, whereas levels of this hormone were found to be significantly lower in young patients with myocardial infarction. These findings may prompt further research into the role played by irisin not only in vascular disorders but also in life span modulation.[46]
Cold exposure increases SIRT1 phosphorylation/activity in both skeletal muscle and BAT, increasing thermogenesis and insulin sensitivity.[47] Elevated SIRT1 levels in people are associated with increased human longevity.[48] SIRT1 (and the other sirtuins) have many metabolic effects, but an important one for improving health and longevity is the fact that SIRT1 increases insulin sensitivity and glucose control in skeletal muscles,[49] triggers the browning of white fat[50] and increases BAT activity.[51]

Some other introduction, 27th of April 2017, also in river Rhine:
Water ca. 12° C, actually in the water (also some minutes after this clip) for about 30 minutes: