Summary
Highlights
The host introduces Professor Keith Baar, a distinguished professor at UC Davis and an expert on how tendons, ligaments, and muscles adapt to training, nutrition, and hormones. The podcast aims to provide clear guidance on training connective tissue, building stronger ligaments, and outlining recovery protocols for calisthenics athletes.
Professor Baar acknowledges familiarity with calisthenics, highlighting 'Hannibal for King' as an example of endurance-based calisthenics. The host then explains various calisthenics disciplines, including street lifting (weighted pull-ups, muscle-ups, dips) and statics (planches, Malteses, levers), emphasizing the stress these movements place on tendons.
Professor Baar explains that most connective tissue injuries are 'jerk-based,' meaning sudden, rapid changes in acceleration or direction. Static movements, often prescribed for tissue health, are less prone to jerk-related injuries compared to dynamic, plyometric movements common in street lifting or competitive sports like Crossfit. He illustrates this with common injuries like tennis elbow, golfer's elbow, and jumper's knee, linking them to high-jerk movements and excessive volume.
The host shares a personal experience of tearing his biceps tendon during a Maltese hold, despite extensive training experience. Professor Baar attributes such injuries to underlying tendon degeneration, noting that studies show no case of a perfectly healthy tendon rupturing. He explains that fatigue, especially in supporting muscles or tendons, can compromise the 'shielding' mechanism of strong tendon parts, leading to injury in weaker areas.
Contrary to popular belief, tendons adapt faster than muscles. Immobilization can lead to a 15-20% loss of collagen in tendons within the first three days, requiring about eight weeks to regrow. The biggest challenge in calisthenics is the absence of delayed onset tendon soreness, making it difficult to gauge overload. Professor Baar clarifies that peak tendon neoprotein synthesis occurs 24-48 hours after activity, but the common misconception about slow tendon adaptation stems from studies involving extreme loads (e.g., 37km run).
Research by Professor Baar's lab, using engineered ligaments, revealed that optimal collagen synthesis is stimulated within about 10 minutes of exercise. Beyond this, the anabolic signal plateaus, while catabolic signals (wear and tear) increase. The most effective protocol involves 10 minutes of exercise, followed by 6-8 hours of rest, repeated up to four times a day for cumulative benefits. This approach, for example, four 10-minute blocks over 24 hours, doubled collagen increase compared to continuous 24-hour stimulation.
Static isometric holds were found to increase tendon strength and size, whereas dynamic movements, even with the same time under tension, resulted in larger but not stronger tendons, and could decrease stiffness, making them more injury-prone. This suggests that static movements offer a better anabolic-to-catabolic signal ratio for tendon strength. He recommends a low-intensity, extended static hold protocol (e.g., one session in the morning) to maximize anabolic signals with minimal catabolic impact, complementing regular training.
The discussion covers optimal intensity. They found that 2% and 4% isometric stretches led to similar strength increases, while 4% dynamic stretches could be detrimental. The key is to achieve a physiological load that generates tension without excessive strain. For anabolic sets, the goal is not progressive overload in terms of weight but maintaining sufficient tension for a minimal effective dose (around 50% body weight for calisthenics movements). This light, consistent loading provides anabolic signals without the high catabolic impact of maximal efforts.
Tendon strength and stiffness depend on collagen content and cross-linking between collagen molecules, mediated by lysol oxidase. This enzyme is inhibited by estrogen and stimulated by testosterone, explaining differences in injury rates and tissue stiffness between sexes. Dynamic and high-intensity movements stimulate lysol oxidase more, increasing cross-linking and stiffness. A combined approach of light isometrics (for collagen synthesis) and higher-load, dynamic movements (for cross-linking) can optimize tendon properties, leading to an additive effect in strength, as seen in climbing studies.
Nutrition provides a 2-5% additive effect over load, which remains the primary driver of tendon adaptation. Hydrolized collagen, especially with vitamin C, can increase tendon size and stiffness. Studies show that a combination of whey protein (for leucine, which activates mTor for protein synthesis) and hydrolized collagen (for glycine and proline, essential amino acids for collagen) offers the best stimulus for collagen synthesis. Timing is crucial: taking collagen and vitamin C 30-60 minutes before exercise maximizes nutrient delivery to tendons, which lack direct blood flow and rely on mechanical pumping of fluid for nutrient exchange. The recommended dose is 5-10 grams of hydrolized collagen with 50-250mg of vitamin C, alongside typical whey protein intake.
Traditional rest and immobilization (RICE protocol) for injuries can be detrimental, leading to significant collagen loss. Instead, Professor Baar advocates for immediate, very light loading after injury, even post-surgery for full tears. This early loading helps maintain collagen and facilitates nutrient exchange, preventing secondary issues like excessive swelling. He gives an example of ankle sprain recovery through gentle 'alphabet' exercises and light inversion holds to pump fluid and stimulate healing in injured tissues, minimizing pain and promoting faster recovery.
For rehabilitation, low-jerk isometric contractions are crucial. This involves slowly applying load (over 3-5 seconds), holding for up to 30 seconds (pain-free), and slowly releasing. This technique targets the injured tissue, stimulating its repair without causing further damage. It's important to continue these isometric exercises for about eight weeks, even if pain subsides quickly, similar to completing a course of antibiotics. Over time, the range of motion improves, and the load can be gradually increased, preparing the tendon for isotonic movements.
The discussion connects tendon physiology to the biopsychosocial model of pain, highlighting how pain is influenced not just by tissue damage but also by psychological and social factors. Early, controlled movement after injury helps retrain the brain to interpret signals positively, preventing chronic pain. On the topic of anti-inflammatories, Professor Baar explains that while strong anti-inflammatory medications (like NSAIDs) or ice baths can hinder adaptation by blunt essential inflammatory signals, some natural compounds like turmeric (curcumin) may have a more nuanced effect, potentially benefiting ligaments without broad suppression of inflammatory pathways critical for tissue repair. However, he notes that more specific natural products are under research.
Professor Baar concludes by reiterating the importance of slow, progressive overload in calisthenics to prevent injuries. He emphasizes that for tendons, ligaments, cartilage, and bone, the goal is not to train for hours but to provide a 'minimal effective dose' of load (e.g., short, controlled static holds) to stimulate adaptation. These short, anabolic sessions, ideally done once or twice a day, can be integrated into a mobility routine and effectively bulletproof connective tissues, maintaining elasticity and function while allowing for longer training sessions focused on muscle strength and cardiovascular health.