Debunking Pre-Workout Carbs Myth: New Research on Nutrition and Training

The Overrated Nature of Pre-Workout Carbohydrates

A recent study has shed new light on the long-held belief that consuming carbohydrates before a workout is crucial for optimal performance. This well-designed research involved a group of trained lifters who performed a workout under three different conditions:

1. No carbs
2. Low carbs (0.3g/kg)
3. High carbs (1.2g/kg)

The meals were carefully matched for taste and texture, ensuring that participants were unaware of their carbohydrate intake. The workout consisted of three all-out sets of squats, overhead presses, bench presses, and rows at 80% of 1RM - a conventional full-body routine.

Surprisingly, the results showed no significant differences in performance across the groups. The number of repetitions completed for each exercise and the total repetitions in the entire workout were similar, regardless of carbohydrate intake.

This finding aligns with a recent systematic literature review that found no significant effects of pre-workout carbohydrates on performance when individuals were not training fasted or engaging in extremely high training volumes.

The Placebo Effect of Pre-Workout Carbs

Interestingly, many studies that have shown improved performance with pre-workout carbs often had a fasted control group without a proper placebo. When a placebo is provided, the effect often disappears, suggesting that the benefits of pre-workout carbs may be largely psychological.

This placebo effect highlights the power of belief in athletic performance. If an athlete believes they need carbs before a workout, not receiving them might negatively impact their performance. However, if they believe they've had a proper breakfast (even if it contained no carbs), their performance remains unaffected.

Long-Term Strength Gains and Carbohydrate Intake

The review also found no significant effect of carbohydrate intake on long-term strength gains. This challenges the common belief that pre-workout carbs are essential for muscle growth and strength development.

Why Pre-Workout Carbohydrates May Be Less Necessary Than Thought

There are several reasons why pre-workout carbohydrates might not be as crucial as previously believed:

1. Muscle Glycogen Utilization: During exercise, muscles primarily rely on stored glycogen rather than recently consumed carbohydrates. The glucose stored in muscle tissue is only available for that specific muscle, making pre-workout carbs essentially "too late" to impact performance significantly.

2. Efficient Glycogen Resynthesis: After a workout, the body is highly efficient at replenishing glycogen stores, even with low carbohydrate intakes. This process involves the Cori cycle, which recycles lactate back to glucose and stores it as glycogen.

3. Alternative Energy Systems: Strength training relies heavily on the creatine phosphate system and the aerobic system for energy production. Glycogen and carbohydrates are primarily needed for medium-intensity, medium-duration activities.

4. Rest Intervals: The long rest periods typical in strength training allow for greater reliance on fat oxidation and aerobic energy systems, reducing the demand for carbohydrates.

5. Total Carbohydrate Requirements: Even for intense workouts, the total carbohydrate requirement is relatively low, often less than 100g for most strength training sessions.

Fasted Training: A Viable Option?

A 12-week study took the concept of pre-workout nutrition a step further by comparing fasted training to fed training. Participants either trained after an overnight fast or 1-2 hours after a high-carb breakfast. The total daily macronutrient intakes were similar between groups.

The results were surprising:

• No significant differences in muscle growth (measured by quadriceps muscle thickness)
• No significant differences in strength development (1RM and power measures)
• No significant differences in total workloads during the training program
• No changes in fat mass for either group
• The fasted training group actually gained significantly more fat-free mass (measured by DEXA scans)

These findings challenge previous research suggesting that fasted training might be detrimental to muscle growth and performance. However, it's important to note that this study was conducted on untrained, overweight individuals, which may limit its applicability to serious lifters.

Considerations for Fasted Training

While the results are intriguing, there are some caveats to consider:

1. Participant Complaints: Many participants reported feeling lightheaded and nauseous, which are common complaints among those new to exercise.

2. High Dropout Rate: 25% of subjects dropped out despite only being required to train twice per week.

3. Contrasting Findings: A separate study on seriously trained lifters found no significant difference in muscle growth but did observe impaired strength gains and lower performance in the fasted training group.

4. Long-Term Effects: The gap in performance between fasted and fed training groups widened over time, suggesting that long-term fasted training might eventually impact muscle growth due to reduced total mechanical tension on the muscles.

Despite these considerations, the studies indicate that fasted training is not as detrimental as once thought. For non-competitive athletes or those who prefer fasted training, it remains a viable option.

Post-Workout Cold Exposure: A Recovery Mistake?

While pre-workout nutrition might not be as critical as once believed, post-workout practices can significantly impact recovery and gains. Recent research has highlighted the potential drawbacks of a popular recovery method: cold plunges or ice baths.

A study concluded that cold water immersion "greatly reduces microvascular blood volume, which is strongly related to a lower post-prandial amino acid incorporation in skeletal muscle protein in recreationally active males." In simpler terms, cold exposure after exercise can hinder the muscle-building process.

The Mechanism Behind Cold's Negative Impact

Cold exposure post-workout can:

1. Reduce muscle protein synthesis
2. Impair long-term muscle growth
3. Hinder strength development

The primary issue is that cold exposure essentially puts the recovery process on hold. While this might seem beneficial in reducing swelling and inflammation, these processes are actually crucial for long-term recovery and adaptation.

When Cold Exposure Might Be Beneficial

For Olympic athletes or those training multiple times per day, cold exposure can help maintain short-term performance by delaying swelling and inflammation. However, this comes at the cost of long-term adaptations.

Cold Exposure and Health Outcomes

A scientific review on cold exposure revealed some surprising findings:

1. Cold water immersion caused significant acute inflammation without affecting overall immune function.
2. No significant effects were found on most measures of mood and stress.
3. One study reported better sleep quality after cold exposure, but this was following heat training.
4. An improvement in self-reported quality of life was observed after one month of cold exposure, but this effect wasn't sustained over three months.

The Practical Use of Cold Exposure

While cold exposure may not provide the miraculous benefits some claim, it's not entirely useless. A cold shower can serve as an effective energizer, similar to a shot of adrenaline. It can be particularly useful when feeling fatigued or drowsy after a warm shower.

Optimizing Training Techniques: Lengthened Partials

Moving from recovery strategies to training techniques, new research has provided insights into the effectiveness of post-failure lengthened partials.

A study compared two training approaches for calf raises:

1. Only lengthened partials (bottom part of the movement)
2. Full range of motion (ROM) reps to failure, followed by partial reps to failure

The results showed that performing only lengthened partials led to slightly better gains compared to the full ROM + partials approach. After eight weeks, the lengthened partials group experienced 10% growth versus 7% growth for the full ROM + partials group.

However, it's important to note that the statistical evidence for this difference was weak. The practical takeaway is that if you choose to incorporate lengthened partials, it might be more effective to dedicate entire sets to them rather than using them as a finisher after full ROM sets.

The Science of Muscle Memory

The concept of "use it or lose it" isn't entirely accurate when it comes to muscle. Research has shown that muscles retain some memory of their former size, making it easier to rebuild lost muscle mass compared to building it initially.

Mechanisms of Muscle Memory

1. Myonuclei Retention: When muscles grow, they increase the number of myonuclei (muscle cell nuclei). These additional myonuclei can persist for a long time, possibly permanently, even after muscle atrophy.

2. Neural Adaptations: The improved muscle activation patterns learned during training can persist even after periods of detraining.

3. Proteomic Changes: Certain proteins built during strength training can remain present for months after training cessation.

4. Epigenetic Modifications: Training can lead to changes in gene expression that may persist over time.

Potential Transgenerational Effects

Fascinating new research suggests that some epigenetic changes resulting from exercise might be passed on to offspring. While more research is needed, this raises the intriguing possibility that building significant muscle mass could potentially make it easier for one's children to build muscle as well.

Conclusion

Recent research has challenged many long-held beliefs about nutrition and training:

1. Pre-workout carbohydrates may not be as crucial as once thought for performance and gains.
2. Fasted training can be a viable option for many individuals, with minimal impact on muscle growth and strength development.
3. Post-workout cold exposure might hinder recovery and long-term adaptations.
4. Lengthened partial reps may be more effective when performed as dedicated sets rather than as finishers.
5. Muscle memory involves complex mechanisms that allow for easier muscle regain after periods of inactivity.

As our understanding of exercise physiology and nutrition continues to evolve, it's crucial to stay informed about the latest research. These findings underscore the importance of individualized approaches to training and nutrition, as what works best can vary significantly between individuals.

Remember, while these studies provide valuable insights, they should be considered in the context of your personal goals, preferences, and overall training program. Always consult with a qualified fitness professional or healthcare provider before making significant changes to your exercise or nutrition regimen.

Article created from: https://www.youtube.com/watch?v=Qpi7pWmM35A