Sunday, July 14, 2024

Hot Water (Not Cold) Immersions More Effective For Recovery

Picture from
With the Paris Olympics around the corner, many of my patients have been asking me about recoveryice immersions and the Singapore women's swimming Olympic selection fiasco (no, I am not discussing that).  

A patient I saw yesterday mentioned that an ice immersion recovery center just opened near his home and he was hoping it will help his sore muscles.

Picture from Business Insider by Alexandre Simoes 
I told him that evidence shows that ice baths/ immersions does not help  recovery. In fact cold water immersion after hard exercise suppressed signaling pathways associated with recovery. This suppression lasted several days. In addition, ice bathing reduced the body's muscles uptake of dietary proteins, which is important for growth and cell maintenance. Grgic (2022) showed that cold water immersion reduced exercise related strength gains while (Pinero et al, 2024) showed that ice bathing immediately after weight training inhibited muscle growth.

On the contrary, hot water immersion (below) improved recovery follwing exercise induced muscle damage (Sautillet et al, 2024).

Picture from Newsmeter
Following exercise induced muscle damage, Sautillet and colleagues (2024) put 30 active males through one of the following recovery interventions : cold water immersion (11 degrees Celcius), hot water immersion (41 deg Celsius) and control group of warm-bath (36 deg Celcius).

Quadriceps maximum strength and explosive strength were measured pre, 24 and 48 hours post exercise. Pressure pain threshold (PPT), or was also measured to quantify the recovery from muscle soreness

Here are the results. 48 hours post exercise, quadriceps maximal strength returned to baseline values after both cold and hot water immersions. However, explosive strength levels and PPT (muscle tenderness) returned to baseline levels post 48 hours only after hot water immersion.

In addition, surface electromyography (electrodes) signals from the vastus lateralis (outer quadriceps) was significantly increased following cold water immersion. Meaning more muscle fatigue. Or as patients like to say, their muscles are 'very tight'.

The authors concluded that a single session of hot water immersion (rather than cold water immersion) improved the rate of explosive strength followed exercise induced damage. When explosive power is a key performance requirement, hot water immersion should be preferred over cold.

*Note that the cold bath temperature used in this study (Santillet et al, 2024) was 11 degrees Celcius. Wim Hof (the Dutch iceman), others on Tik Tok, other social media and purveyors of commercial health and wellness have different protocols.

For those who are keen the temperature of the hot bath was 41 degrees Celsius for a duration of 15-30 minutes.


Grgic J. (2023). Effects Of post-exercise Cold-water Immersion On Resistance Training-Induced Gains In Muscular Strength: A Meta-analysis. Eur J Sp Sci. 23(3): 372-308. DOI: 10.1080/17461391.2022.2033851.

Pinero A, Burke R, Augustin F et al (2024). Throwing Cold Water On Muscle Growth: A Systematic Review With Meta-analysis Of The Effects Of Postexercise Cold Water Immersion On Resistance Training-induced Hypertrophy. Eur J Sp Sci. 24: 177-189. DOI: 10.1002/ejsc.12074

Sautillet B, Bourdillon N, Millet GP et al (2024). Hot Bt Not Cold Water Immersion Mitigates The Decline In Rate Of Force Development Following Exercise-Induced Muscle Damage. Med Sci Sp Ex. DOI: 10.1249/MSS.0000000000003513

Sunday, July 7, 2024

Can Ozempic And Wegovy Help Knee Osteoarthritis Pain?

Picture from Second Nature 
I never thought I would be reading up on Ozempic and Wegovy. I have a patient who told me he started taking Ozempic as he's trying to lose weight. They are both injected medications that contain semaglutide. Ozempic is approved (in USA) to treat Type II diabetes while Wegovy is a higher dosed version (of semaglutide) that is approved (again in USA) for weight loss.

According to results from the STEP-9 trial (by Novo Nordisk) reported at the World Congress on Osteoarthritis (OARSI 2024), Wegovy, containing peptide receptor agonist (GLP-1) semaglutide not only induced weight loss but improved knee pain in people with knee osteoarthritis (OA).

STEP-9 was a multi national, multi center phase 3 clinical trial that enrolled subjects that had a BMI of >30, a clinical diagnosis of knee osteoarthritis with moderate radiographic changes and were experiencing knee pain.

There were 407 subjects in STEP-9, randomly allocated 2:1 to receive once a week a subcutaneous injection of either semaglutide 2.4 mg or a placebo for a total of 68 weeks. Mean age of the subjects were 56 years and 81.6 percent were women. 60.9 percent were White, 11.8 percent Native American, 7.6 percent Black and 19.7 percent were of other ethnic origin.

Another finding was that the use of pain medication went down in the semaglutide group compared to the placebo group. This was maintained throughout the study.

Of course the are suggestions that the weight loss itself helped with the knee pain since weight loss fell by a significantly greater amount in the people treated with semaglutide versus those given a placebo. Weight loss was 13.7 percent versus 3.2 percent from baseline after 68 weeks.

The authors questioned if there is a specific action of GLP-1 receptor agonist on the knee joint itself and not through weight loss only. Especially since results from previous LOSEIT trial using liraglutide (also used to treat Type II diabetes) showed that subjects lost 2.8 kg versus a gain of 1.2 kg in the placebo group over a year did not have any change in the Knee injury and Osteoarthritis Outcome scores. The patients in that study had to undergo weight loss first before they were given the liraglutide.

Obesity is a worsening problem world wide in developed countries and Singapore has increasing numbers in people with diabetes. This is certainly going to add to the boom in weight loss drugs.

Morgan Stanley projects that the market for weight loss drugs will reach $54 billion by 2030, a 400 percent increase from today. Especially since so many celebrities have gushed about how much weight they have lost since taking them. Eli Lilly and Novo Nordisk (who owns Wegovy and Ozempic) together have at least 12 more obesity medications under development.

We are living through a cultural shift in which obesity is viewed as a disease rather than the result of lifestyle choices. 

Should my patient try Wegovy instead especially since he does have knee pain from osteoarthritis? Wegovy has a higher dose of 2.4 mg semaglutide versus 2 mg for Ozempic.

Will Wegovy or Ozempic be the new default recommended treatment for osteoarthritis pain instead of surgery, gel injections and physiotherapy?


*Please note that the STEP-9 study was funded by Nova Nordisk and the principal investigator Henning Bliddal acknowledged that research grants were given by Novo Nordisk to his institution as well as consulting fees and honoraria. He also received congress and travel support from Contura