Cold plunges: what the evidence really shows

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1. 1

   Strategic Application of Post-exercise Cold-Water Immersion to Enhance Performance Recovery and Adaptation: An Umbrella Review of 15 Published Systematic Reviews with Meta-analysis.

   Sports medicine - open (Berjisian et al.)Published Sep 30, 2026Checked Oct 4, 2026

   “Post-exercise CWI resulted in significant improvements in muscular power at 24 h post-high-intensity exercise and at 24-48 h post-eccentric exercise, and in jump performance at 24-48 h, despite impaired jump performance in the initial hours after post-exercise CWI. Endurance performance improved immediately after CWI, but CWI produced no later benefits or positive effects on adaptations. CWI did not improve muscular strength performance, and impaired strength and hypertrophic gains. CWI improved heart rate variability immediately after exercise, reduced muscle soreness up to 96 h, and lowered creatine kinase (CK) concentrations between 24 and 72 h, with no significant effects on C-reactive protein or interleukin-6 up to 72 h. No immediate impact on blood lactate or lactate dehydrogenase was found, although some reductions appear 24-72 h post-exercise.ConclusionsPost-exercise CWI confers outcome-specific recovery benefits but may impair resistance training adaptations with chronic use. These findings support a periodised, context-driven approach to CWI implementation rather than routine application after all exercise sessions.”

2. 2

   The cold-water immersion recovery-adaptation paradox: Reconciling acute parasympathetic and analgesic benefits with chronic hypertrophy attenuation.

   Experimental physiology (Tornero-Aguilera et al.)Published Aug 29, 2026Checked Oct 4, 2026

   “Acute CWI (10-15°C, 10-15 min) consistently augments parasympathetic reactivation, reduces soreness within 24-72 h (network meta-analytic SUCRA 88%) and modulates inflammatory time-courses. In parallel, equivalent protocols attenuate post-resistance-exercise mechanistic target of rapamycin complex 1 signalling, ribosomal biogenesis and satellite-cell-mediated myonuclear addition, translating into reduced type II fibre cross-sectional area and modest impairments of strength gain (effect size -0.23). Endurance-related microvascular and mitochondrial adaptations appear less affected and may be selectively enhanced. A protocol-by-goal decision framework links CWI parameters - water temperature, duration, body coverage and temporal placement - to expected adaptive outcomes across hypertrophy, strength, endurance and concurrent training contexts. CWI is neither uniformly beneficial nor uniformly harmful; its effects are predictable and depend on the training goal. CWI should be used when fast recovery between sessions matters most, and withheld after resistance training when muscle growth is the main goal of the training block.”

3. 3

   Cold-water exposure and psychological outcomes in adults: a systematic review and meta-analysis.

   Frontiers in physiology (Ngandeu et al.)Published Sep 16, 2026Checked Oct 4, 2026

   “Sensitivity analyses were conducted where possible.ResultsThirteen studies including 4105 participants met inclusion criteria. Pooled estimates generally favored CWE for depressive symptoms, perceived stress, wellbeing, and mood or affect, but confidence intervals were wide and several estimates attenuated in controlled-only analyses. Anxiety showed little evidence of consistent benefit. Additional outcomes, including sleep, cortisol, heart rate, and pain, were sparse but generally directionally favorable. Most studies had high, serious, or critical risk of bias.ConclusionThe available evidence does not establish that CWE improves mood, depressive symptoms, perceived stress, wellbeing, or related outcomes. The evidence remains limited, heterogeneous, and at substantial risk of bias, and several estimates became smaller in controlled only analyses. CWE should not currently be regarded as a standalone treatment for psychiatric disorders. Larger controlled trials are needed to clarify clinical relevance, safety, mechanisms, and optimal use.Systematic review registrationhttps://www.crd.york.ac.uk/PROSPERO/, identifier CRD420250654531.”

4. 4

   Temperature-dependent effects of post-exercise cold-water immersion on recovery: a systematic review and meta-analysis

   BMC Sports Science Medicine and Rehabilitation (Jeon & Yeo)Published Jul 31, 2026Checked Oct 4, 2026

   “The meta-analysis demonstrated that CWI produced statistically significant moderate-to-large effects on DOMS, CK, and Mb during the post-exercise recovery period (DOMS: SMD = − 0.81; CK: SMD = − 0.64; Mb: SMD = − 0.93; all p < 0.001). Subgroup analyses by water temperature showed numerically smaller reductions in DOMS at ≈5 °C (SMD = − 0.2) compared with ≈10 °C (SMD = − 0.8) and ≈15 °C (SMD = − 0.9); however, the difference between temperature subgroups was not statistically significant ( p = 0.79). CK and Mb were significantly reduced across all temperature ranges, with no significant differences between temperature subgroups. On average, CWI was associated with reductions in DOMS, CK, and Mb, although substantial heterogeneity and wide prediction intervals indicate that these effects may not be consistently reproduced across settings. Numerically larger reductions in DOMS were observed at approximately 10–15 °C than at ≈5 °C, but neither subgroup analysis nor meta-regression confirmed a temperature-dependent effect. No water-temperature range can currently be considered superior. Not applicable. Not prospectively registered.”

5. 5

   Post‐exercise cold water immersion attenuates acute anabolic signalling and long‐term adaptations in muscle to strength training

   The Journal of Physiology (Roberts et al.)Published Jul 14, 2015Checked Sep 30, 2026

   “Isokinetic work (19%), type II muscle fibre cross‐sectional area (17%) and the number of myonuclei per fibre (26%) increased in the ACT group (all P < 0.05), but not the CWI group. In another study, nine active men performed a bout of single‐leg strength exercises on separate days, followed by CWI or ACT. Muscle biopsies were collected before and 2, 24 and 48 h after exercise. The number of satellite cells expressing neural cell adhesion molecule (NCAM) (10−30%) and paired box protein (Pax7) (20−50%) increased 24–48 h after exercise with ACT. The number of NCAM + satellite cells increased 48 h after exercise with CWI. NCAM + ‐ and Pax7 + ‐positive satellite cell numbers were greater after ACT than after CWI ( P < 0.05). Phosphorylation of p70S6 kinase Thr421/Ser424 increased after exercise in both conditions but was greater after ACT ( P < 0.05). These data suggest that CWI attenuates the acute changes in satellite cell numbers and activity of kinases that regulate muscle hypertrophy, which may translate to smaller long‐term training gains in muscle strength and hypertrophy. The use of CWI as a regular post‐exercise recovery strategy should be reconsidered.”

6. 6

   Effects of cold-water immersion on health and wellbeing: A systematic review and meta-analysis

   PLoS ONE (Cain et al.)Published Jan 29, 2025Checked Sep 30, 2026

   “Eleven studies were included, comprising 3177 total participants and a mean PEDro score of 6.4 (n = 7 moderate quality, n = 4 high quality). CWI interventions were performed in baths (n = 10) or showers (n = 1) at temperatures ranging from 7°C to 15°C and durations ranging from 30 seconds to 2 hours. The meta-analysis revealed significant increases in inflammation immediately (SMD: 1.03, [95% CI: 0.37, 1.68], p < 0.01) and 1 hour post CWI (SMD: 1.26, [95% CI: 0.59, 1.94], p < 0.01), indicating an acute inflammatory response. This systematic review suggests that CWI delivers time-dependent effects on inflammation, stress, immunity, sleep quality, and quality of life, offering potential practical applications for health practitioners considering CWI for stress management and wellbeing support. However, the current evidence base is constrained by few RCTs, small sample sizes, and a lack of diversity in study populations.”