Study Details

This 4-week intervention examined whether modest protein overfeeding altered body composition in 35 exercise-trained men and women who completed pre- and post-testing 🔍

Participants were asked to increase protein intake by ~20% while maintaining habitual training and keeping carbohydrate and fat intake similar 🥩

Key Findings

📈 Actual protein intake increased by ~12%, from 1.93 → 2.12 g/kg/day (+18 g/day)

⚖️ Total energy intake increased by only ~51 kcal/day and did not change significantly

💪 Lean body mass increased by +0.67 kg over 4 weeks

💧 Total body water also increased by +0.49 L, which is important because body composition was measured using bioelectrical impedance

↔️ Fat mass did not significantly change (+0.37 kg), while body fat percentage also remained statistically unchanged

📊 Total body mass increased by ~0.57 kg, but this did not reach statistical significance

🧬 Researchers also examined the obesity-associated FTO rs9939609 genotype, but risk-allele status did not predict changes in lean mass, fat mass, body weight or body fat percentage

🏋️ Importantly, participants already had relatively high baseline protein intakes and averaged ~5 h/week of resistance training

⚠️ The study had no control group, only 35 of 56 participants completed the intervention, dietary intake was self-reported and BIA is sensitive to hydration status

Conclusion

For trained athletes already consuming plenty of protein, a modest increase from ~1.9 to ~2.1 g/kg/day may support small increases in lean mass without promoting fat gain, although the rise in body water and lack of a control group mean the true magnitude of muscle gain remains uncertain ✅

Reference

https://www.tandfonline.com/doi/full/10.1080/15502783.2026.2744348

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Study Details

This new crossover study examined how cold-water immersion (CWI) and alternating cold + sauna exposure affected cognition and metabolism in 20 healthy, active adults 🔍

Participants completed 10 min of CWI at 10°C, contrast therapy alternating 2 min of 10°C water and an 82°C sauna, or a thermoneutral control 🧊

Key Findings

🔥 Five minutes after exposure, fat oxidation was higher after CWI (0.17 g/min) than contrast therapy (0.11 g/min) or control (0.09 g/min)

⏱️ The CWI effect was short-lived, with no significant difference from control by 20 min

🔥 Contrast therapy showed a more delayed response, with higher fat oxidation than control 20 min after exposure

🚴 During subsequent cycling at 20–30% Wmax, contrast therapy increased fat oxidation versus control by approximately 0.13–0.15 g/min

🧠 CWI improved reaction time from baseline and produced faster reactions than contrast therapy immediately afterwards

↔️ However, reaction time after CWI was not significantly faster than control immediately post-exposure

📉 Contrast therapy was associated with poorer processing speed later in testing, suggesting alternating hot and cold exposure may not offer the same cognitive effect

🫀 During low-intensity cycling, heart rate was approximately 10 bpm lower after contrast therapy than control

🌡️ Core temperature and perceived exertion did not differ between conditions

⚠️ The study included only 20 active adults, measured acute responses only and did not assess exercise performance or fat loss

Conclusion

For athletes, brief cold-water immersion may provide a short-lived increase in alertness and fat oxidation, while alternating sauna and cold exposure may prolong changes in low-intensity fat oxidation; neither finding currently demonstrates an improvement in sporting performance ✅

Reference

https://researchdirects.com/index.php/strengthandperformance/article/view/229

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Study Details

This study examined how an 8-day training camp in hot conditions affected energy intake, macronutrient intake and hunger in 22 well-trained endurance athletes 🔍

Fourteen athletes completed matched training periods in temperate conditions (10°C, 58% humidity) and then hot conditions (30°C, 74% humidity) 🏃

A control group of 8 athletes completed both periods in the same temperate environment ↔️

Key Findings

🔥 During the heat camp, daily energy intake increased by ~24%

🍞 Carbohydrate intake increased by ~36%, representing the largest macronutrient change

🥩 Protein intake also increased by ~28%

🍳 Breakfast was the main point of adjustment: energy intake rose by ~90%, carbohydrate by ~107% and protein by ~70%

🌙 Protein intake was also higher at dinner during the hot-weather camp

🥤 Energy, carbohydrate and protein consumed during training sessions all increased significantly in the heat

😋 Athletes reported greater hunger before breakfast, which may partly explain why this meal accounted for much of the additional intake

↔️ None of these measures changed between training periods in the control group

⚠️ The sample was small, the heat group completed the conditions in a fixed order, and the study measured food intake rather than energy balance, recovery or performance

Conclusion

For endurance athletes attending hot-weather training camps, breakfast and during-session fuelling may become particularly important opportunities to increase energy, carbohydrate and protein intake to support the combined training and environmental demands ✅

Reference

https://www.tandfonline.com/doi/full/10.1080/02640414.2026.2754629?scroll=top&needAccess=true

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Study Details

This controlled study examined how 10 days of unilateral leg unloading affected muscle protein synthesis (MPS), muscle protein breakdown (MPB) and muscle size in 14 healthy young women 🔍

One leg was unloaded for 10 days, while the opposite leg continued to receive resistance exercise 🦵

Key Findings

📉 MRI showed a significant reduction in vastus lateralis volume in the unloaded leg, confirming short-term muscle atrophy

🧮 Researchers compared traditional steady-state calculations with non-steady-state modelling that accounted for the shrinking muscle protein pool

↔️ Both modelling methods produced the same overall interpretation

📉 Mixed-muscle MPS declined significantly during unloading

🧬 The response was protein-fraction specific: myofibrillar MPS decreased, while sarcoplasmic MPS remained unchanged

↔️ Muscle protein breakdown did not increase, suggesting atrophy was not driven by greater protein degradation

🏋️ In the loaded leg, mixed, myofibrillar and sarcoplasmic MPS remained unchanged compared with baseline across the measurement period

💡 Short-term disuse therefore appears to reduce the construction of new muscle protein rather than substantially accelerate the breakdown of existing tissue

🙋‍♀️ The study adds valuable female-specific evidence to a research area that has often relied heavily on male participants

⚠️ The sample was small and involved only healthy young women using a 10-day unloading model, so findings may not fully translate to longer immobilisation, severe injury or older adults

Conclusion

For women, during injury-related unloading, maintaining as much safe mechanical loading as possible should be prioritised, with nutrition used to support that stimulus rather than assuming muscle loss is mainly caused by accelerated protein breakdown ✅

Reference

https://physoc.onlinelibrary.wiley.com/doi/10.1113/JP292118

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Study Details

This case study used doubly labelled water to measure energy expenditure during a 200-km open-water swim completed over 73.5 hours by a 103-kg former Olympic-level swimmer 🔍

Key Findings

🔥 Total energy expenditure averaged 14,747 kcal/day, reaching approximately 46,600 kcal across the 76-hour measurement period

📈 This equated to 6.17 times basal metabolic rate, placing it among the highest directly measured sustained energy expenditures reported over a similar duration

🌊 The swim took place in 20.5°C water, where continuous conductive heat loss likely added substantially to the metabolic cost of near-continuous swimming

🥣 The athlete consumed around 10,000 kcal/day, using gels, bananas, muesli bars, sports drinks and larger meals approximately every 4 hours

📉 Despite this, the estimated cumulative energy deficit was still approximately 16,600 kcal

⏱️ Nutrition was provided every 20 minutes during brief stops, helping maintain intake without substantially interrupting progress

💧 Daily water turnover reached 14.8 L, equivalent to approximately 0.61 L/hour

💪 The athlete completed an estimated 200,000 strokes, contributing to shoulder pain, blisters and substantial upper-body mechanical stress

😴 Total rest time was around 7 hours, including partial sleep, across the event

↩️ A previous attempt ended after 163 km and 55 hours, when intake was only ~5700 kcal/day and sleep totalled around 40 minutes

⚠️ This involved one athlete, and calculating expenditure required assumptions about respiratory exchange ratio, so the exact values remain uncertain

Conclusion

For extreme multi-day endurance events, success depends not only on physical capacity, but on sustaining very high energy intake alongside realistic pacing, planned sleep, thermal protection and frequent, practical feeding opportunities ✅

Reference

https://www.sciencedirect.com/science/article/pii/S1728869X26000894?via%3Dihub

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Study Details

This systematic review and dose–response meta-analysis included 24 randomised controlled trials and 2,068 adults, examining whether walnut intake influences inflammatory cytokines and adipokines 🔍

Key Findings

📉 Walnut consumption produced a small reduction in C-reactive protein (CRP) versus control (WMD = −1.0 mg/dL)

🧬 Interleukin-6 (IL-6) was also modestly reduced (WMD = −0.11 pg/mL)

↔️ However, sensitivity analyses showed that these findings were not robust when several influential studies were removed

🔥 Walnuts did not significantly reduce tumour necrosis factor-alpha (TNF-α)

⚖️ There were also no significant effects on the adipokines adiponectin or leptin

📆 Subgroup analyses suggested stronger anti-inflammatory effects in interventions lasting more than 12 weeks

🥜 Effects also appeared more pronounced with walnut intakes above 50 g/day, although this does not establish an optimal dose

🧩 Walnuts provide polyunsaturated fats, fibre and antioxidants, which may help explain potential effects on inflammatory pathways

⚠️ The average effects were modest, study results were not entirely stable, and the clinical importance of the changes remains uncertain

Conclusion

Adding walnuts to an overall high-quality diet may provide a small anti-inflammatory benefit, but these findings do not show that walnuts directly improve exercise recovery or performance ✅

Reference

https://pubmed.ncbi.nlm.nih.gov/42947498/

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Study Details

This systematic review included 6 randomised placebo-controlled trials and 118 participants, examining creatine during immobilisation and rehabilitation 🔍

Key findings ⬇️

Key Findings

🛑 Studies used 1–2 weeks of upper- or lower-limb immobilisation, mainly in healthy people aged 15–24 years

🥄 Protocols commonly used 20 g/day for 5–7 days, followed by 3–5 g/day during rehabilitation

📉 Direct imaging showed similar quadriceps losses with creatine and placebo: −5.6% vs −5.5% after 1 week and −11.0% vs −9.4% after 2 weeks

⚖️ Two studies reported better preservation of limb lean mass, but these used DXA or bioelectrical impedance, which can be influenced by fluid shifts and may not reflect preserved muscle tissue

💪 Effects on strength, power and endurance during immobilisation were inconsistent, with favourable findings mainly from small upper-limb studies

🏋️ Results were more promising once structured resistance rehabilitation began

📈 One study found greater quadriceps growth with creatine during rehabilitation (+21.3% vs +14.3%)

⚡ Other studies reported greater improvements in lower-limb lean mass, power, strength or muscular endurance, although benefits were inconsistent

↔️ Passive recovery without structured retraining showed no creatine benefit

⚠️ Evidence was limited and heterogeneous, with no trials in older adults or clinical populations at greater risk of prolonged muscle loss

Conclusion

For injured athletes, creatine should not be relied upon to prevent atrophy during complete immobilisation, but it may be worth continuing or introducing alongside progressive resistance-based rehabilitation, where the limited evidence is more encouraging ✅

Reference

https://pubmed.ncbi.nlm.nih.gov/42952382/

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Study Details

This structured narrative review included 19 articles, examining creatine, beta-alanine and their co-supplementation for endurance athletes 🔍

Key findings ⬇️

Key Findings

🧬 Beta-alanine increases muscle carnosine and intracellular buffering, potentially delaying fatigue when glycolytic demand is high

⏱️ Its clearest value may be in efforts lasting 1–10 min, or longer races containing threshold work, repeated surges, climbs and finishing sprints

📈 Some studies improved time to exhaustion, 10-km running or late-race sprint power, but several found no benefit for time trials or VO₂max

🥄 The review suggests 3.2–6.4 g/day for ≥4 weeks, divided into smaller doses to reduce paraesthesia

⚡ Creatine may support repeated high-intensity efforts through greater phosphocreatine availability, ATP resynthesis and buffering capacity

🍞 It may also enhance carbohydrate-mediated glycogen resynthesis and potentially reduce muscle damage and inflammation

🚴 Benefits appear most plausible in cycling, triathlon and tactically variable events involving repeated accelerations or decisive sprint finishes

🏃 Any transient body-mass increase may matter more in weight-bearing events such as running

↔️ Creatine has not consistently improved VO₂max, lactate threshold, time to exhaustion or overall endurance performance

🧪 Combining creatine and beta-alanine has not shown a clear additional benefit for aerobic capacity or endurance performance

⚠️ Most evidence comes from untrained, recreational or moderately trained participants, with little direct research in elite endurance athletes

Conclusion

For endurance athletes, creatine and beta-alanine are best periodised around high-intensity training or races involving surges, climbs and sprint finishes, rather than treated as universal supplements for steady-state endurance ✅

Reference

https://pubmed.ncbi.nlm.nih.gov/42959925/

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Study Details

This randomised 11-week study compared endurance, resistance and concurrent training in 30 trained young men, examining lower-body strength, explosive performance and muscle morphology 🔍

Training comprised 5 weeks emphasising maximal strength, followed by 6 weeks targeting explosive strength 📆

Key Findings

💪 Maximal voluntary isometric contraction increased only with resistance training (+18.4%), suggesting concurrent training may limit maximal-strength development

⚡ Peak rate of force development improved with resistance (+31.8%) and concurrent training (+23.1%)

⏱️ Resistance training produced progressive improvements across both phases, whereas concurrent training improved mainly during the second

🚀 Early-phase force development (0–50 ms) improved earlier with resistance training, while the concurrent group improved only from mid- to post-training (+38.3%), alongside greater quadriceps activation

🆙 Countermovement-jump positive impulse increased with resistance (+12.7%) and concurrent training (+8.8%), with no evidence of interference

📈 Vastus lateralis cross-sectional area increased with resistance (+17.0%) and concurrent training (+8.8%)

🧬 Muscle pennation angle also increased in both groups: +18.6% with resistance and +10.1% with concurrent training

↔️ Endurance training alone produced no improvements in rate of force development

⚠️ The study was small, included only trained young men and lasted 11 weeks

Conclusion

For trained athletes, concurrent endurance and resistance training may constrain maximal isometric strength and delay rapid-force adaptations, but well-periodised resistance training can still produce meaningful hypertrophy and explosive-performance gains alongside endurance work ✅

Reference

https://pubmed.ncbi.nlm.nih.gov/42926218/

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Study Details

This systematic review included 16 studies, with 7 entered into meta-analyses, examining whether exogenous ketone supplementation improves recovery after exercise 🔍

Key findings ⬇️

Key Findings

😣 Exogenous ketones did not significantly reduce muscle soreness compared with control (SMD = 0.39)

🍞 Muscle glycogen resynthesis was also not significantly improved (SMD = 18.21), with substantial uncertainty around the estimate

🩸 Post-exercise lactate concentrations were slightly lower in the control conditions, although the difference was small and considered unlikely to be clinically meaningful

💪 Creatine kinase, a commonly used marker of muscle damage, was not significantly affected

🧠 Evidence for cognitive recovery was mixed, with isolated improvements in reaction time but most cognitive outcomes remaining unchanged

↔️ Overall, the findings do not support a consistent benefit for soreness, glycogen restoration, muscle-damage markers or cognitive recovery

🧩 Supplement protocols, exercise models and recovery measurements varied considerably between studies, making direct comparisons difficult

👨 Most participants were physically active men, substantially limiting generalisation to women and other athletic populations

⚠️ The evidence base was relatively small, and only 7 of the 16 included studies provided data suitable for meta-analysis

📊 The authors conclude that current evidence suggests limited recovery benefits from exogenous ketones, with further well-powered studies needed across more diverse populations and recovery settings

Conclusion

For athletes, exogenous ketones should not currently be expected to meaningfully accelerate post-exercise recovery, and established strategies such as sufficient carbohydrate, protein, fluids and sleep remain the priorities ✅

Reference

https://pubmed.ncbi.nlm.nih.gov/42958814/

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Study Details

This narrative review examined nutrition, glucose monitoring, training and competition considerations for competitive swimmers with type 1 diabetes (T1D) 🔍

Here are the key takeaway messages ⬇️

Key Findings

🩸 Glycaemic responses vary by session type: aerobic swimming generally lowers glucose, while anaerobic/high-intensity work may increase or stabilise it

📊 Continuous glucose monitoring (CGM) can help guide fuelling and insulin strategies, but exercise-related lag means readings should be interpreted cautiously

🍞 Carbohydrate intake should be periodised to training load: roughly 3–7 g/kg/day for one daily session and 6–10 g/kg/day with ≥2 sessions

⚡ During longer sessions, 30–60 g carbohydrate/hour may be appropriate, with higher-intensity sessions also requiring adequate pre-exercise fuelling

💉 Insulin adjustments are highly session-specific, with larger bolus reductions generally required for longer aerobic work than for sprint or resistance sessions

🌙 Enhanced insulin sensitivity can persist for 24–48 h post-exercise, increasing the risk of late and nocturnal hypoglycaemia

🥛 Post-exercise recovery should prioritise carbohydrate for glycogen restoration, alongside protein; the review suggests 1.2–1.6 g/kg/day protein

🧃 Fast-acting carbohydrate should always be available, and hypoglycaemia should be treated promptly before returning to exercise

🏔️ Altitude may increase carbohydrate oxidation and hypoglycaemia risk, requiring closer monitoring and potentially greater carbohydrate provision

☕ Caffeine may reduce the fall in glucose during exercise, but responses are unpredictable and sleep effects should also be considered

⚠️ Evidence specific to elite swimmers with T1D remains sparse, with many recommendations extrapolated from other sports and general T1D guidance

Conclusion

For swimmers with T1D, the priority is not a fixed carbohydrate or insulin formula, but repeatedly practising session-specific combinations of fuelling, insulin adjustment and glucose monitoring until responses become as predictable as possible ✅

Reference

https://pubmed.ncbi.nlm.nih.gov/42931559/

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Study Details

This randomised trial examined whether creatine supplementation alongside 6 weeks of high-intensity resistance training influenced cognition, sleep and menopause-related symptoms in 51 perimenopausal women 🔍

Participants were allocated to creatine (n=18), placebo (n=20), or non-training control (n=13) 🏋️

Creatine and placebo groups completed a 5-day loading phase at 20 g/day, followed by ~4.5 g/day maintenance, alongside twice-weekly progressive resistance training 🥄

Key Findings

🧠 Stroop reaction time improved over the 6 weeks, but there were no between-group differences in cognitive performance

🩸 During the Stroop test, prefrontal oxygenation increased with creatine by +0.32%, while it decreased with placebo by −1.62%

😴 Sleep consistency improved more with creatine, with a baseline-adjusted advantage of +7.4 percentage points versus placebo at week 6

🌡️ Creatine was also associated with fewer self-reported temperature-sensitivity days

↔️ The abstract does not report clear benefits for memory performance or other menopause-related symptoms such as fatigue, soreness, brain fog or bloating

⌚ Sleep and symptoms were monitored daily using WHOOP wearables, while cognition was assessed with Stroop and Rey 15-item memory testing

⚠️ The intervention was short, the sample relatively small, and creatine was combined with resistance training, meaning the findings do not isolate creatine in a completely sedentary context

Conclusion

For perimenopausal women undertaking resistance training, creatine may offer benefits beyond muscle by improving sleep consistency and cerebral oxygenation, but larger and longer trials are needed before treating these effects as established ✅

Reference

https://pubmed.ncbi.nlm.nih.gov/42926218/

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Study Details

This narrative review included 16 placebo-controlled studies, examining whether ashwagandha supplementation influences body mass, fat mass, lean mass, muscle size and anthropometric measures in adults 🔍

Key findings ⬇️

Key Findings

⚖️ The clearest potential benefit was in overweight or obese adults, where several studies reported greater reductions in body mass, BMI or waist circumference versus placebo

📉 In one 8-week trial, 600 mg/day KSM-66® reduced body mass by 2.32 kg versus 1.13 kg with placebo

📆 A 24-week study using the same dose reported an 8.46 kg reduction in body mass, compared with 2.41 kg for placebo

🔥 Evidence for reducing body fat percentage was inconsistent; only one of several studies found a significant additional reduction versus placebo

💪 Evidence for increasing lean mass, fat-free mass or muscle mass was also largely negative, with no included study demonstrating a clear benefit using these measures

📏 Two resistance-training studies did report greater increases in arm and chest circumference, although circumference is a less robust measure of muscle growth than DXA or BIA

🏋️ The apparent muscle-size benefits therefore have not been confirmed as greater gains in actual lean or muscle mass

🧬 Proposed mechanisms include reductions in cortisol and stress-related eating, improved glucose and lipid metabolism, and possible increases in testosterone, but these mechanisms remain partly theoretical or preclinical

↔️ Effects appear less convincing in healthy, already active or trained adults than in those with excess body mass

⚠️ Studies varied substantially in population, extract, dose, training and dietary intervention, and 4 of the 16 studies had commercial sponsorship

📊 The authors conclude that current evidence is mixed and not strong enough to recommend ashwagandha specifically for improving body composition

Conclusion

For athletes, ashwagandha may support stress or other performance-related outcomes, but there is currently little evidence that it reliably increases lean mass or reduces body fat beyond the effects of training and nutrition alone ✅

Reference

https://pubmed.ncbi.nlm.nih.gov/42931579/

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What is Super Digestible?

Every day I post a research breakdown of the latest nutrition science related to human performance, health and the power of food. The daily 1-min reads are a great way to stay on top of the research. But, I want to make actionable summaries even more accessible 📝

Therefore, I started Super Digestible, a monthly newsletter containing a one-to-two sentence summary of each study I’ve reviewed that month. Focusing specifically on how you can apply these findings in your own practice ✅

Each study will be filtered into: DO, CONSIDER, DON’T. Based on the research findings, paired with my professional experience in the world of elite sport 🏆

This is your monthly research cheat sheet, so you can stay at the very pinnacle of science-based performance nutrition 🏔

A huge shoutout to who inspired this format. I highly recommend following Daniel’s Endurance: Ideas & Implementation Substack.

The Super Digestible newsletter is a paid subscriber special. If you’re not a paid subscriber yet but want to know more, check out the January 2025 edition for free!

Each item is linked to the original research breakdown. Just click on the DO, CONSIDER, DON’T 👈

Please note that paid subscribers have access to all previous research breakdowns via the Performance Archive 📚

✅ DO these things…

DO: Incorporate plant-based foods such as beetroot, cherries, berries and other polyphenol-rich options as part of post-exercise recovery strategies, especially for reducing muscle soreness 🌱

DO: Before implementing any specific or costly recovery strategy, be aware that time is the most important recovery modality, make sure you have enough rest between sessions before trying to enhance recovery through alternate means ⏳

DO: Consume >8 g/kg/day for 36–48 hr as a practical carbohydrate-loading target to maximise muscle glycogen stores ahead of endurance exercise 🍝

Read more

Study Details

This systematic review and meta-analysis included 17 studies and 257 participants, examining the effect of giving athletes a placebo while telling them it was caffeine 🔍

Key findings ⬇️

Key Findings

☕ Across primary performance outcomes, “placebo caffeine” produced a small-to-moderate improvement versus baseline (d = 0.49)

⏱️ The largest pooled effect was for time to exhaustion (d = 1.07), although this was based on only 2 studies

😮‍💨 Perceived exertion improved moderately (d = 0.52), suggesting expectation may make exercise feel easier

🏋️ Placebo caffeine also increased repetitions performed (d = 0.48) and total weight lifted (d = 0.73)

↔️ Effects on power output, velocity, heart rate, lactate and oxygen consumption were not significant

🧠 Placebo effects were larger when researchers were blinded to whether participants had actually received caffeine, suggesting researcher expectations may also influence outcomes

📣 Using more strategies to reinforce the belief that caffeine would improve performance was associated with larger reductions in RPE

🙋‍♂️ Effects appeared larger in studies with fewer women, but 82% of participants were male, making sex differences highly uncertain

📊 Between-study heterogeneity was low (I² = 21%), and results were not driven by any single study

⚠️ However, 9/17 studies were high risk of bias and the remaining 8 had unclear risk, resulting in low overall certainty

Conclusion

Interestingly, the pooled placebo effect (d = 0.49) sits within the range previously reported for actual caffeine, suggesting some of caffeine’s ergogenic effect may come from expectation alongside its pharmacological effects 🧐

For athletes, believing caffeine will work may meaningfully contribute to its performance benefit, so familiarisation, positive expectations and a consistent caffeine routine could help maximise the effect of actual caffeine use ✅

Reference

https://pubmed.ncbi.nlm.nih.gov/42897966/

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Study Details

This randomised, double-blind crossover study examined whether acute sodium bicarbonate improved outdoor 10-km running performance in 21 recreational female runners 🔍

Participants completed two 10-km outdoor track time trials after sodium bicarbonate or placebo 🏃

Sodium bicarbonate was consumed at 0.3 g/kg body mass, compared with 0.03 g/kg salt as placebo 🧂

Both treatments were taken alongside a standardised carbohydrate-rich meal providing 1.5 g/kg carbohydrate 🍚

Supplementation and the meal were consumed 90 min before running ⏱️

Key Findings

📈 Blood bicarbonate increased from 22.2 → 27.7 mmol/L with sodium bicarbonate, while blood pH increased from 7.42 → 7.47

🏃 10-km completion time was significantly faster with sodium bicarbonate: 3046.1 vs 3078.4 seconds

🩸 Blood lactate was also higher after sodium bicarbonate at rest and throughout exercise, consistent with greater extracellular buffering and glycolytic contribution

🤢 Importantly, GI symptoms did not differ between conditions, suggesting the protocol was well tolerated

🩸 Trials were completed during the same phase of the menstrual cycle, helping reduce within-participant hormonal variability

💡 The study extends bicarbonate research beyond short, high-intensity exercise by showing a benefit during a prolonged endurance event performed under field conditions

⚠️ The sample was relatively small and limited to recreational female runners, so the findings should not automatically be generalised to elite athletes or other populations

Conclusion

For runners, 0.3 g/kg sodium bicarbonate taken with a carbohydrate-rich pre-race meal 90 min before exercise may be a practical way to improve 10-km performance without necessarily increasing GI symptoms ✅

Reference

https://pubmed.ncbi.nlm.nih.gov/42926128/

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Study Details

This narrative review examined research from 2013–2026 on the gut microbiota, exercise performance and recovery, including human, animal and experimental s…

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Study Details

This systematic review and network meta-analysis included 19 r…

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Study Details

This review examined 16 common diet questions and misconceptions using trials, reviews and meta-analyses 🔍

Here are the 16 key takeaways ⬇️

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Study Details

This 2026 ISSN position stand reviewed major dietary approaches for reducing body weight and fat mass in healthy, active and athletic adults 🔍

H…

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