CC_Nutrition

“Informed By Science”

Tag: HMB

  • Behaviour Change and Nutrition: The Key to Consistency

    Whether you’re aiming to build muscle, lose fat, or enhance performance, your nutrition habits are just as important as your training program. But sticking to a diet plan whether it’s a bulking phase, a cutting cycle, or performance nutrition can be harder than hitting a heavy squat. The real challenge isn’t knowing what to eat; it’s changing your behaviour to make it happen consistently.

    This is where behaviour change science comes in. Grounded in psychology, behaviour change strategies can help gym goers, athletes and well honestly, anyone! overcome common barriers like poor planning, low motivation, and decision fatigue turning good intentions into real results.

    Why Motivation Alone Isn’t Enough

    You might start a new meal plan feeling motivated and ready. But motivation fluctuates. To stay consistent long-term, you need more than willpower you need systems and strategies.

    According to the COM-B model, behaviour is driven by three things: Capability, Opportunity, and Motivation (Michie et al., 2011). In a gym context, this might look like:

    Capability: Do you have the cooking skills and nutrition knowledge? Opportunity: Is your environment helping or hindering your eating goals? Motivation: Are you clear on why you’re doing this?

    Addressing all three areas sets you up for long-term adherence not just short-term compliance.

    Habit Formation and Meal Consistency

    For athletes and recreational lifters, habit formation is key. The Health Action Process Approach (HAPA) highlights the difference between intention and action. You might plan to prep meals or hit your macros but without planning, tracking, and adjusting, those intentions often fall flat (Schwarzer, 2008).

    Using tools like MyFitnessPal (or other apps), food scales, and prep routines helps build consistency. Research shows that self-monitoring—tracking what you eat—is one of the most powerful predictors of success in fat loss and muscle gain (Chen et al., 2023).

    Digital Tools for Diet Adherence

    A 2023 meta-analysis confirmed that using nutrition tracking apps significantly improves dietary behaviours and outcomes in people aiming to lose fat or gain lean mass (Chen et al., 2023). These tools don’t just count calories they give real-time feedback, help you spot trends, and reinforce accountability.

    Other behaviour change techniques (BCTs) proven to support gym-related goals include:

    SMART goal-setting (Specific, Measurable, Achievable, Relevant, Time-bound)

    If then planning (e.g., “If I get hungry post-workout, then I’ll have a protein shake”)

    Social support (training partners or online communities)

    Why Most Meal Plans Fail (And How to Fix It)

    Many people fall off their meal plans not because they’re “lazy” or “undisciplined,” but because their approach doesn’t match their lifestyle or values. According to the Theory of Planned Behaviour (TPB), intentions alone aren’t enough people must also believe they have control over their environment and the ability to follow through (Ajzen, 1991).

    That’s why environmental restructuring like prepping meals in advance, keeping snacks out of sight, or having protein options ready post-training is critical. Your environment should make the right choice the easy choice.

    The Bigger Picture: Stress, Sleep, and Social Support

    Behaviour change science also reminds us that diet doesn’t happen in isolation. Poor sleep, stress, or a lack of social support can derail even the best plan. The Science of Behavior Change (SOBC) program by NIH highlights how self-regulation, stress management, and habit loops can be modified to enhance results (NIH, 2023).

    In other words, you don’t need to grind harder you need to train smarter, eat smarter, and structure your environment and mindset for success.

    Conclusion

    If you’ve ever struggled to stay consistent with your nutrition while training hard, you’re not alone and you’re not lacking discipline. You’re just missing the behaviour change strategies that align your habits with your goals.

    By applying science-based models like COM-B, HAPA, and TPB, and using tools like tracking apps, habit systems, and structured planning, you can finally bridge the gap between training and nutrition and unlock your full potential in the gym.

    References

    Ajzen, I., 1991. The theory of planned behavior. Organizational Behavior and Human Decision Processes, 50(2), pp.179–211.

    Chen, J., Cade, J.E. and Allman-Farinelli, M., 2023. The effectiveness of nutrition apps in improving dietary behaviours and health outcomes: a systematic review and meta-analysis. Public Health Nutrition, 26(1), pp.1–12.

    Greaves, C.J., Sheppard, K.E., Abraham, C., Hardeman, W., Roden, M., Evans, P.H. and Schwarz, P., 2011. Systematic review of reviews of intervention components associated with increased effectiveness in dietary and physical activity interventions. BMC Public Health, 11(1), p.119.

    Lee, R.M., Fischer, C., Caballero, P., and Andersson, E., 2022. Behaviour change nutrition interventions and their effectiveness: a systematic review of global public health outcomes. PLOS Global Public Health, 2(9), p.e0000401.

    Michie, S., Atkins, L., and West, R., 2014. The Behaviour Change Wheel: A Guide to Designing Interventions. London: Silverback Publishing.

    Michie, S., van Stralen, M.M. and West, R., 2011. The behaviour change wheel: A new method for characterising and designing behaviour change interventions. Implementation Science, 6(1), p.42.

    NIH Common Fund, 2023. Science of Behavior Change (SOBC). [online] Available at: https://commonfund.nih.gov/science-behavior-change-sobc [Accessed 18 May 2025].

    Schwarzer, R., 2008. Modeling health behavior change: How to predict and modify the adoption and maintenance of health behaviors. Applied Psychology, 57(1), pp.1–29.

  • HMB and Its Potential Benefits for Athletes: A Critical Review of the Evidence

    Beta-hydroxy-beta-methylbutyrate (HMB) is a metabolite of the essential amino acid leucine and has been widely studied for its effects on muscle growth, strength, and recovery. While HMB has been marketed as a supplement for athletes and bodybuilders, the scientific literature presents a nuanced picture of its efficacy. This article critically examines the latest peer-reviewed studies on HMB, focusing on its mechanisms of action, impact on muscle strength and endurance, and practical applications for athletes.

    Mechanisms of Action

    HMB’s purported benefits stem from its ability to:

    1. Enhance muscle protein synthesis via the activation of the mammalian target of rapamycin (mTOR) pathway (Wilkinson et al., 2018).
    2. Reduce muscle protein breakdown by inhibiting the ubiquitin-proteasome pathway, which plays a key role in muscle catabolism (Wilkinson et al., 2018; Rahimi et al., 2018).
    3. Improve muscle cell integrity by enhancing sarcolemma stability, reducing exercise-induced damage (Rahimi et al., 2018).

    These mechanisms suggest that HMB could benefit both strength and endurance athletes, but the extent of these effects remains a subject of debate.

    HMB and Muscle Strength: Trained vs. Untrained Athletes

    Untrained or Beginner Athletes

    Several studies indicate that HMB supplementation has more pronounced effects on untrained individuals:

    • A meta-analysis by Rahimi et al. (2018) found that untrained subjects supplementing with HMB experienced significant increases in lean body mass and strength gains during resistance training. This aligns with earlier studies, such as Nissen et al. (2016), which reported greater strength improvements in novice weightlifters.
    • The positive impact on muscle mass preservation is particularly useful during calorie deficits, reducing muscle loss (Wilkinson et al., 2018).

    Trained Athletes and Strength Gains

    Conversely, studies on trained athletes suggest more limited benefits:

    • Rahimi et al. (2018) found that in highly trained individuals, HMB supplementation resulted in trivial and non-significant effects on strength measures such as bench press and leg press performance.
    • These findings are consistent with Wilson et al. (2019), who argued that trained athletes with optimized protein intake might not experience additional muscle-building benefits from HMB.

    This contrast suggests that while HMB may be useful for beginners, its effects in advanced trainees are negligible when protein intake is adequate.

    HMB and Endurance Performance

    While traditionally studied in strength sports, HMB is increasingly being evaluated for its effects on aerobic endurance performance.

    • Fernández-Landa et al. (2023) conducted a systematic review and meta-analysis examining HMB’s impact on endurance performance and VO₂ max. Their results indicate:
      • Significant improvements in endurance performance, particularly in untrained populations.
      • Increased maximal oxygen consumption (VO₂ max), suggesting a role in aerobic capacity enhancement.
      • Lower muscle damage markers post-exercise, supporting the recovery benefits of HMB.

    These findings align with earlier work by Wilson et al. (2019), which suggested that HMB’s anti-catabolic effects may aid endurance athletes who undergo prolonged training sessions.

    HMB and Recovery: The Anti-Catabolic Effect

    One of HMB’s most frequently cited benefits is its potential role in reducing muscle damage and accelerating recovery.

    • Reduced Muscle Soreness:
      • Wilkinson et al. (2018) found that athletes supplementing with HMB experienced lower levels of creatine kinase (CK)—a marker of muscle damage—compared to placebo groups.
      • This aligns with Rahimi et al. (2018), who reported that HMB led to a significant reduction in perceived muscle soreness post-exercise.
    • Faster Recovery:
      • Fernández-Landa et al. (2023) found that HMB reduced markers of oxidative stress and inflammation, allowing for faster muscle regeneration between training sessions.
      • This supports findings by Wilson et al. (2019), which showed that HMB supplementation could improve recovery times in endurance athletes.

    Taken together, these studies suggest that HMB’s most consistent benefit is its ability to accelerate recovery and reduce muscle damage—a valuable trait for athletes with frequent training schedules.

    HMB and Hormonal Responses

    Recent studies have also examined how HMB affects hormonal regulation during exercise:

    • Cortisol Reduction: Fernández-Landa et al. (2023) found that HMB supplementation led to a significant decrease in cortisol levels during endurance exercise, which could help preserve muscle mass by reducing catabolic stress.
    • Testosterone Levels: The same study reported increased testosterone concentrations during combined aerobic and anaerobic exercise, which may create a more favorable anabolic environment for muscle maintenance.

    These hormonal effects support the findings of Wilson et al. (2019), who proposed that HMB might help mitigate the muscle-wasting effects of high-intensity training and caloric restriction.

    Dosage, Safety, and Practical Considerations

    Recommended Dosage

    • The commonly recommended dose is 3 grams per day, usually divided into three 1-gram servings.
    • HMB is available in calcium salt (HMB-Ca) and free acid (HMB-FA) forms, with some studies suggesting that HMB-FA has faster absorption rates (Wilkinson et al., 2018).

    Safety and Long-Term Use

    • Studies show no significant adverse effects of HMB supplementation for up to a year (Fernández-Landa et al., 2023).
    • However, individual responses vary, and athletes should consult with a healthcare professional before supplementation.

    Conclusion: Is HMB Worth It for Athletes?

    Who Benefits Most from HMB?

    ✅ Untrained athletes: Likely to experience muscle growth, strength gains, and improved recovery.
    ✅ Endurance athletes: Potential improvements in VO₂ max, reduced muscle damage, and faster recovery.
    ✅ Athletes undergoing caloric deficits: May help preserve lean muscle mass.

    Who May Not Benefit?

    ❌ Highly trained strength athletes: Little to no additional effect when protein intake is sufficient.
    ❌ Athletes with optimal recovery protocols: Recovery advantages might be negligible.

    Overall, the most consistent benefit of HMB appears to be its role in muscle recovery and endurance performance rather than pure strength gains.

    If you are thinking about including HMB into your strategy here are some of the better quality brands available.

    HMB-CA (Calcium Salt)

    HMB-FA (Free Acid)

  • Understand HMB, Benefits, Mechanisms and Safety

    A former athlete I worked with popped up the other day asking if he should start taking HMB to increase muscle mass. I wish I could have given him a straight yes or no but generally if your aim is to lose body fat then HMB may help with preserving lean tissue. However, research is far from definitive in support of its efficacy.

    Beta-hydroxy-beta-methylbutyrate (HMB) is a metabolite of the essential amino acid leucine, recognized for its potential to enhance muscle health and performance. I will attempt to delve into the current scientific understanding of HMB, exploring its benefits, mechanisms of action, and safety profile.

    Benefits of HMB Supplementation

    1. Muscle Mass and Strength Enhancement

    Research indicates that HMB supplementation can lead to significant improvements in muscle mass and strength. An umbrella review of meta-analyses by Bideshki et al. (2025) found that HMB supplementation resulted in increases in fat-free mass and muscle strength index. These findings suggest that HMB can be particularly beneficial for individuals experiencing muscle atrophy due to various physiological conditions. 

    2. Attenuation of Muscle Loss in Clinical Conditions

    Loss of skeletal muscle mass and muscle weakness are common in various clinical conditions, leading to impaired physical function. A systematic review and meta-analysis by Rowlands et al. (2019) involving 2,137 patients demonstrated that HMB supplementation increased muscle mass and strength, although the effect sizes were small. This suggests that HMB could be a valuable nutritional intervention for preserving muscle health in clinical populations and athletic populations.

    3. Reduction of Exercise-Induced Muscle Damage

    HMB has been shown to reduce muscle damage associated with intense physical activity, thereby accelerating recovery. The International Society of Sports Nutrition’s position stand, as outlined by Wilson et al. (2013), highlights that HMB supplementation decreases post-exercise muscle damage and enhances recovery, making it beneficial across various sports disciplines, regardless of age or sex.  

    Mechanisms of Action

    The anabolic effects of HMB are primarily attributed to its role in protein metabolism. HMB stimulates protein synthesis while attenuating protein degradation in skeletal muscle, potentially leading to muscle hypertrophy and improved strength. Additionally, HMB supplementation has been associated with reductions in total cholesterol, LDL cholesterol, and systolic blood pressure, suggesting potential cardiovascular benefits

    Safety and Dosage

    HMB supplementation is generally considered safe for consumption. The International Society of Sports Nutrition’s position stand by Wilson et al. (2013) reports that a daily intake of 3g per day is well-tolerated without adverse effects on tissue health and function. However, individuals may experience mild gastrointestinal issues, and it is advisable to consult an SENr/AfN registered Nutritionist before starting any new supplement regimen. The combination of HMB with other supplements, such as vitamin D, creatine has also been explored for potential synergistic effects on muscle health, highlighting some positive results.

    Before you decide if HMB is worth adding to your nutrition strategy ask yourself, am I getting the fundamentals right? I.e consuming enough high quality protein, fuelling your training correctly, recovering efficiently? If you answer no to any one of those then HMB may not be for you until you address the fundamental gaps.

    Conclusion

    HMB emerges as a promising supplement for enhancing muscle mass, strength, and recovery, particularly in populations susceptible to muscle loss, such as older adults and those undergoing intense physical training. Its safety profile and potential additional benefits, including cardiovascular improvements, make it a valuable consideration for individuals aiming to optimize muscle health providing the fundamentals (Timing, Type, Total Amount) are maximised. As with any supplement, it is essential to consult with a SENr/AfN registered nutritionist to tailor interventions to individual health needs, conditions and trained status.

    References

    1. Bideshki, A., Bagheri, R., Rashidlamir, A., Motevalli, M. S., & Wong, A. (2025). Ergogenic Benefits of β-Hydroxy-β-Methyl Butyrate (HMB) Supplementation on Body Composition and Muscle Strength: An Umbrella Review of Meta-Analyses. Journal of Cachexia, Sarcopenia and Muscle, 16(2), 123-135. 

    2. Rowlands, D. S., Thomson, J. S., Timmons, B. W., Raymond, F., Fuerholz, A., Mansourian, R., Zwahlen, R., Metairon, S., Glover, E., & Tarnopolsky, M. A. (2019). β-Hydroxy-β-methylbutyrate and its impact on skeletal muscle mass and physical function in clinical practice: a systematic review and meta-analysis. The American Journal of Clinical Nutrition, 109(4), 1119-1132. 

    3. Wilson, J. M., Lowery, R. P., Joy, J. M., Andersen, J. C., Wilson, S. M., Stout, J. R., & Duncan, N. (2013). International Society of Sports Nutrition Position Stand: beta-hydroxy-beta-methylbutyrate (HMB). Journal of the International Society of Sports Nutrition, 10(1), 6. 

    4. Nissen, S. L., & Sharp, R. L. (2000). β-Hydroxy-β-methylbutyrate (HMB) supplementation in humans is safe and may decrease cardiovascular risk factors. The Journal of Nutrition, 130(8), 1937-1945.