1. Hausswirth C, Le Meur Y, Bieuzen F, Brisswalter J, Bernard T. Pacing strategy during the initial phase of the run in triathlon: influence on overall performance. Eur J Appl Physiol. Apr 2010;108(6):1115-1123.
Age related declines are evident in real life as much as sport. Studies suggest peak age for athletics is 35 years of age, with some exceptions (Dara Torres, hopefully not synthetically enhanced, but I have my doubts)4. Muscle force, endurance, power and aerobic capacity have been documented to decrease 1-2% per year following peak performances (sorry to be the bearer of bad news). These numbers are suggested values in sedentary individuals, luckily there are mechanisms to prevent age related declines. The most prominent decline is in type II muscle fibers (fast twitch muscle fibers). If these muscle fibers are lost most frequently in adults, why are most Master's swimmers apprehensive to do sprint swimming which engages the most of these diminishing muscles fibers? Seriously, anyone I'm still waiting for a good rebuttal. One can argue that performing sprint exercises can be advantageous towards musculoskeletal injuries, but with proper warm-up and exercise progression there is no more risk of injury than overuse injuries secondary to pounding yardage. Moreover, injuries with sprinting are typically muscle strains which heal well with proper managed healing, opposing overuse injuries (rotator cuff tendonitis) can be dehabilitating injuries which may recover with proper management, but is much more complex and typically involves surgeries in later life. I have a few swimmers that swim to stay in shape and loose weight, this is great and important for a healthy lifestyle. However their opinion to loose weight involves swimming 4,000 yards in 1 hour. A lot of their arguments are catered around the notion that moderate exercise burns the most fat, which is true...but (there is always a but) moderate exercise burns less calories. Lets do the math, if moderate exercise burns 65% fat and 35% carbohydrates, but high intensity exercise burns 40% fat, 60% carbohydrates. Once again, theoretically moderate exercise is superior, but lets do the math
Table 1: These total values are estimates1
Calories from Fat
Watching TV for 60 minutes
Swimming easy for 60 minutes
Sprinting and strong swimming for 60 minutes
There is my rant on sprinting and calories burned. The article today compares age related declines in the top 10 times for Olympic and Ironman distance triathlons. The study only looked at males over two seasons (2006-2007). First, I will discuss the physisiological response to aging, how it affects the different aspects of a triathlon and how to prevent these disadvantageous changes.
Adaptations Secondary to Aging
As stated, aging decreases the amount of type II (type IIx more specifically) muscle fibers. Type II fibers are the big, explosive muscle fibers, when these fibers are lost muscle mass and strength decrease termed sarcopenia. It is estimated lean muscle mass during adolescence is 50% of body weight, aging declines lean body mass to 25% at ages between 70-80. During sarcopenia, type II fibers may atrophy (shrink in size), transition towards type I fibers, or decrease the volume of satellite cells3. Satellite cells are essential in protein turnover in muscle, more specifically when exercising your muscle are constantly breaking down and rebuilding. This impressive mechanism is one of a kind that damages itself to get stronger, simply unorthodox! Satellite cells are needed during rebuilding of muscles and a decreased volume leads to less rebuilding (don't worry we can help them out, stay tuned).
How are Triathlons Influenced
The main finding in the study noted by Lepers et al. was cycling had the smallest age related decline in performance compared to swimming and running4. Secondly, the study believes running and cycling had a larger relative decrease in performance in the Ironman than the Olympic distance triathlon, but swimming had a similar decline with increased distance4. The reason cycling had the smallest decline in performance is likely due to a variety of reasons. First, it has the least amount of stress on the body. Cycling is low impact allowing athletes to perform high volumes of training without orthopaedic injuries. Orthopaedic injuries are the second hypothesis it has the smallest decline compared to swimming and running. Swimming and running have multiple orthopedic (knee, hips, shoulder) injuries associated with them, but when was the last time you heard of someone being hurt while cycling, other than falling off a cliff on the Santa Monica mountains? The last hypothesis cycling holds off time declines is cycling does not use a stretch shortening cycle which relies on more type II fibers. A stretch shortening cycle occurs when the body utilizes eccentric muscle contraction. For example, the hamstring is the predominant muscle in the back of your thigh. The hamstring is composed of three muscles (biceps femoris, semimembranosus, semitendinosis…in case you were wondering) and their primary collective action is to flex the knee. The most common cause of a hamstring strain is from the “eccentric use of the hamstring” while running. The eccentric use of the hamstring is highest when your leg is extending, off the ground, and swinging forward prior to hitting the ground for your next step. This stage is termed the “terminal swing” (and yes, we realize these sounds more like a carnival ride than a leg movement). The eccentric load is highest due to the amount of stretch it places on the hamstring muscles (this is similar to the strain you feel in a straight leg raise). Eccentric contraction is used in swimming during recovery of the arm in all the strokes, as well as kicking. During kicking, the downkick in freestyle, the hamstrings are contracting eccentricly as they stretch across the hip and pelvis. Eccentric contraction requires less energy, but generates more force requiring type II muscle fibers which are typically decreased in older adults.
The old adage, “if you don't use it you loose it” is making a comeback like skinny jeans. To prevent muscle loss resistance training has been proven to reduce the detrimental effects of changing by increasing strength by 174% after 8 weeks. Resistance training can enhance satellite cells, allowing muscles to rebuild. A high intensity, multi-joint lifting program utilizing maximal lifts is the most beneficial and can be performed safely, if it is monitored properly and increases in loads and volumes are made correctly.
Next, it is essential to fuel the system. Once again, older adults naturally loose muscle mass therefore more protein to prevent these changes. The current daily recommendations for protein consumption are .8g/kg of body weight. These values were derived from younger persons, current research protein consumption for older adults needs to be higher, roughly 1.0-1.25 g/kg of body weight to prevent sarcopenia. Information protein timing after a workout can be read in an earlier post found here: http://www.swimmingscience.net/2010/02/weights-wednesday-post-resistance.html. Lastly protein with the 10 essential amino acids, especially leucine, enhances protein synthesis3. Here is a list of foods high in leucine, thank you http://www.dietaryfoodfiber.com.
Leucine food sources Leucine content (grams/ 100 gram food) 2
Soybeans, mature seeds, raw
cowpea, catjang, mature seeds, raw
Beef, round, top round, separable lean and fat, trimmed to 1/8" fat, select, raw
Beef, top sirloin, separable lean only, trimmed to 1/8" fat, choice, raw
Peanuts, all types, raw
Salami, Italian, pork
Fish, salmon, pink, raw
Crustaceans, shrimp, mixed species, raw
Chicken, broilers or fryers, thigh, meat only, raw
Egg, yolk, raw, fresh
Chickpeas (garbanzo beans, bengal gram), mature seeds, raw
Seeds, sesame butter, tahini, from raw and stone ground kernels
Chicken, broilers or fryers, wing, meat and skin, raw
flax seed, raw
Nuts, walnuts, english
Egg, whole, raw, fresh
Egg, white, raw, fresh
Sausage, Italian, pork, raw
Milk, sheep, fluid
Pork, fresh, separable fat, raw
Milk, goat, fluid
Milk, whole, 3.25% milkfat
Soy milk, fluid
Snap beans, green, raw
Milk, human, mature, fluid
The goal of this paper was not to dwell on the declines of aging. These declines are inevitable, but with the right plan and execution reducing these declines are possible. The more muscle mass embodied, the more one has to decline before detrimental effects are noticed and I challenge each Master’s swimmer and coach to safely push themselves to achieve levels that are atypical for their age!
1. Leucine: food sources high in amino acid leucine. | amino-acids. http://www.dietaryfiberfood.com/leucine-rich.php. Accessed March 10, 2010.
2. Busting the Great Myths of Fat Burning - For Dummies. 2009; http://www.dummies.com/how-to/content/busting-the-great-myths-of-fat-burning.html. Accessed March 10, 2010.
3. Koopman R, van Loon L. Aging, exercise, and muscle protein metabolism. J Appl Physiol. Jun 2009;106(6):2040-2048.
4. Lepers R, Sultana F, Bernard T, Hausswirth C, Brisswalter J. Age-Related Changes in Triathlon Performances. Int J Sports Med. Feb 2010.
- The mean improvement with short term caffeine ingestion was 6.5-9.4%.
- Individual variation influences caffeine effectiveness.
Supplements for Swimmers
- Astorino, Todd A; Roberson, Daniel W Efficacy of Acute Caffeine Ingestion for Short-term High-Intensity Exercise Performance: A Systematic Review Journal of Strength and Conditioning Research:January 2010 - Volume 24 - Issue 1 - pp 257-265.
- OD and ID athletes have similar injury rates despite different training.
- Triathletes, OD more than ID, have a higher risk for Achilles tendon injuries.
- All athletes, especially triathletes, that keep training logs should record workouts with "work:rest" ratios. For example, in swimming 5x100 maximum efforts 4:1 work to rest. This simple means if you were going 1:00 on the 100 maximum effort you would rest 15 seconds.
- Swimming effort influences biking performance.
- Peeling P, Landers G.Swimming intensity during triathlon: a review of current research and strategies to enhance race performance.J Sports Sci. 2009 Aug;27(10):1079-85.