A Scientific Overview of Cold Therapy Techniques for Metabolism
Cold exposure has been shown in a number of studies to increase metabolism through a process called thermogenesis where brown fat tissue is activated to produce heat energy. However, there are two types of thermogenesis: non-shivering thermogenesis and shivering thermogenesis. Non-shivering thermogenesis is triggered by the release of adrenaline and epinephrine as a result of cold exposure. Shivering thermogenesis occurs when the skin’s temperature receptors detect a sudden drop in temperature sending a message to the hypothalamus in your brain which will send a signal to the muscles to rapidly contract and relax to produce heat. These involuntary contractions will cause the release of a chemical called succinate which will further stimulate brown fat to be converted into heat energy, increasing overall metabolism.
Step-by-step Protocol to Boost Metabolism through Ice Baths:
1. Temperature:
There is no exact temperature range an ice bath should be at to boost metabolism rather it is vital that the ice bath is uncomfortable. For some individuals this may be a temperature of 15°C, some 10°C and some even lower. It is important that the ice bath is uncomfortable as if you are acclimated to the temperature your body won’t release as much adrenaline and epinephrine as well as shiver therefore less thermogenesis will occur.
2. Duration:
To maximise shivering you should spend intermittent spells in the ice bath. This would be as follows:
1. Get into the ice bath and wait till you start shivering.
2. Now spend a further 1-3 minutes in the ice bath whilst shivering.
3. Once this time is up, exit the ice bath and wait 1-3 minutes before re-entering the ice bath. It is important to not dry yourself during this time.
4. Repeat this process 3 times.
3. Frequency
Studies have shown that anywhere between 1-5 ice bath sessions a week is enough to increase metabolism.
4. Time of day:
There is no evidence to suggest having an ice bath at a specific time of day will be more effective at boosting metabolism.
5. Progression:
You should only progress your ice bath temperature and duration gradually. This is because if you do it too fast you may become acclimated to colder temperatures and shorter durations in the ice bath.
(Huberman, 2021)
Here’s a comprehensive breakdown of recent studies investigating the effect of cold exposure on metabolism:
1. Altered brown fat thermoregulation and enhanced cold-induced thermogenesis in young, healthy, winter-swimming men.
Objective:
The purpose of this observational study is to examine the difference in brow fat tissue activation between winter swimmers and non-winter swimmers when exposed to the cold.
Theory:
Frequent cold exposure leads to physiological adaptations in winter swimmers which improve their ability to generate heat. Such as increased thermogenesis (conversion of fat tissue to heat energy) and fat tissue distribution.
Findings:
Winter swimmers were found to burn between 500-1000 calories more then non-winter swimmers over the course of a day when they had undergone cold exposure that same day. Their bodies where also found to rely more on burning fat than glucose for heat energy. Indicating they may have adapted to alter their fat metabolism to cope with cold exposure.
(Søberg et al, 2021)
2. Temperature-acclimated brown adipose tissue modulates insulin sensitivity in humans.
Objective:
The aim of this study was to investigate how varied temperature exposure (19-27°C) impacted brown fat activation, calories burnt and metabolism in 5 healthy adult males.
Theory:
This study proposed a variety of reasons why colder temperatures would lead to increased thermogenesis including:
– Stimulates the thyroid glands to release hormones such as adrenaline and epinephrine which will activate brown fat.
– Increased adiponectin in the blood stream which is a chemical that will improve insulin sensitivity and increase glucose metabolism.
– White fat tissue will be converted to beige fat tissue (a combination of both white and brown) which means that a greater amount of fat tissue is available for thermogenesis.
Findings:
When exposed to colder temperatures adult males have higher levels of thermogenesis. This study also states there may be a link between thermogenesis and glucose metabolism which could mean thermogenesis could be used as a tool to improve metabolic health.
(Lee et al, 2014)
3. Effect of Acute Cold Exposure on Energy Metabolism and Activity of Brown Adipose Tissue in Humans: A Systematic Review and Meta-Analysis.
Objective:
This systematic review aimed to investigate the effect of cold exposure on energy expenditure and brown fat tissue activation in humans.
Theory:
Cold exposure increases brown fat activation which increases metabolism resulting in fat tissue being broken down for heat energy.
Findings:
Both acute and long term cold exposure lead to increases in brown fat tissue activation and metabolism. However, long term cold exposure was found to lead to increased appetite resulting in it having little impact on overall weight loss. This study states that cold exposure may be a viable method to treat obesity when combined with other strategies such as diet and exercise.
(Huo et al, 2022)
4. Effect of repeatedly applied cold water immersion on subclinical atherosclerosis, inflammation, fat accumulation and lipid profile parameters of volunteers
Objective: This study had a total of 25 participants and investigated the effect of one hour of daily cold exposure via air or water compared to those who had no cold exposure at all for a duration of two months.
Theory: When exposed to cold a process called non-shivering thermogenesis where brown fat tissue is rapidly converted into heat energy causing a sudden significant increase in metabolic rate. Frequent cold exposure leads to physiological adaptations such as the recruitment of more mitochondria leading to more brown adipose tissue formation.
Findings: Those who underwent cold exposure had a higher metabolic rate, larger amount of brown adipose tissue and did not gain weight unlike the group of participants who did not undergo any cold exposure.
(Romu et al, 2024)
Conclusion:
These studies highlight how cold exposure’s positive effects on fat loss can enhance our overall health. This is as decreased insulin sensitivity and increased insulin resistance is associated with a lower risk of developing type 2 diabetes as well as healthier cholesterol being associated with improved cardiovascular health. Additionally, these studies do have some potential drawbacks and highlight the need for higher quality studies to develop more conclusive evidence for cold exposure and fat loss.
References:
1. Søberg, S., Löfgren, J., Philipsen, F. E., Jensen, M., Hansen, A. E., Ahrens, E., Nystrup, K. B., Nielsen, R. D., Sølling, C., Wedell-Neergaard, A. S., Berntsen, M., Loft, A., Kjær, A., Gerhart-Hines, Z., Johannesen, H. H., Pedersen, B. K., Karstoft, K., & Scheele, C. (2021). Altered brown fat thermoregulation and enhanced cold-induced thermogenesis in young, healthy, winter-swimming men. Cell reports. Medicine, 2(10), 100408. https://doi.org/10.1016/j.xcrm.2021.100408
2. Lee, P., Smith, S., Linderman, J., Courville, A. B., Brychta, R. J., Dieckmann, W., Werner, C. D., Chen, K. Y., & Celi, F. S. (2014). Temperature-acclimated brown adipose tissue modulates insulin sensitivity in humans. Diabetes, 63(11), 3686–3698. https://doi.org/10.2337/db14-0513
3. Huo, C., Song, Z., Yin, J., Zhu, Y., Miao, X., Qian, H., Wang, J., Ye, L., & Zhou, L. (2022). Effect of Acute Cold Exposure on Energy Metabolism and Activity of Brown Adipose Tissue in Humans: A Systematic Review and Meta-Analysis. Frontiers in physiology, 13, 917084. https://doi.org/10.3389/fphys.2022.917084
4. Romu, T., Vavruch, C., Dahlqvist-Leinhard, O., Tallberg, J., Dahlström, N., Persson, A., Heglind, M., Lidell, M. E., Enerbäck, S., Borga, M., & Nystrom, F. H. (2016). A randomized trial of cold-exposure on energy expenditure and supraclavicular brown adipose tissue volume in humans. Metabolism: clinical and experimental, 65(6), 926–934. https://doi.org/10.1016/j.metabol.2016.03.012
5. Huberman, A. (2021). How to Lose Fat with Science-Based Tools. https://www.hubermanlab.com/episode/how-to-lose-fat-with-science-based-tools
