Triathlon – The Finer Details
Swimming mainly utilises the latissimus dorsi, deltoids, pectoralis, and triceps however the gluteal muscles, hamstrings, and abdominal muscles are also engaged. Freestyle is often the chosen stroke by triathletes, it is a full body movement and hence training of all these muscle groups is critical for a swimmer or triathlete. Furthermore, the most common freestyle movement is internal shoulder rotation and hence the muscles that stabilise this joint are critical for this athlete, these muscles include the supraspinatus, subscapularis, infraspinatus, and teres minor. Stabilising these will help prevent common shoulder swimming injuries, such as ‘swimmers’ shoulder’.[1]
Although cycling is typically considered non-weight bearing, the long periods of training and racing can lead to overuse injuries. Studies have shown that 85% of cyclists report an overuse injury with the most common being neck and knee pain. Knee pain that is common in cyclists is often caused by tight or strong knee extensor muscles (quadriceps and gluteal muscles) which are the dominant muscles used in cycling performance. Tightness in these areas can pull on the patella causing anterior knee pain. Other common movement patterns whilst cycling include hip extension and ankle stabilisation.[2]
Running is a highly dynamic and repetitive movement that can result in overuse injuries in the Achilles tendon and plantar fascia. Running injuries are predominately lower limb (approximately 60%)[3]. The most common movement patterns in running include knee flexion and extension as well as dorsi and plantar flexion.[4]
Studies have shown that 87% of long course athletes experience injury due to overuse within a 26-week training program[5]. Across the 3 sports, evidence indicates similar injury rates for cycling and running (43% and 50% respectively), whereas swimming tended to have a much lower injury rate of around 7%[6].
During an ironman triathlon, it is estimated that athletes can expend up to 11,000 calories. Due to the endurance nature of these events, the utilisation of the anaerobic-PC and anaerobic-lactic are minimal, and hence the main energy system required for optimal performance is the aerobic system[7]. Frequent hard accelerations and decelerations are relatively uncommon in long distance triathlon hence why the anaerobic system is not heavily utilised. Regarding pacing changes, data shows that optimal performance often involves consistent pacing, however the power output does randomly fluctuate throughout the course of a race due to conditions, course terrain and movements by other competitors[8]. It is also suggested that elite athletes adapt a ‘positive pacing’ strategy in which each successive lap or over the course of a discipline the pace continues to decrease, potentially due to a decrease in neuromuscular activity and the gradual depletion of glycogen stores[9]. This consistent pacing or gradual change over several hours further reinforces the importance for an efficient aerobic system to consistently supply the body with ATP.
REFERENCES
[1] Monu JM. Sport-specific training for a competitive freestyle sprint swimmer. Strength & Conditioning Journal. 2013 Oct 1;35(5):48-55.
[2] So RC, Ng JK, Ng GY. Muscle recruitment pattern in cycling: a review. Physical therapy in sport. 2005 May 1;6(2):89-96.
[3] Luna NM, Alonso AC, Bocalini D, Borin G, Brech GC, Greve JM. Analysis of acceleration time of ankle in long-distance runners and triathletes. MedicalExpress. 2017 Jul;4.
[4] Novacheck TF. The biomechanics of running. Gait & posture. 1998 Jan 1;7(1):77-95.
[5] Andersen CA, Clarsen B, Johansen TV, Engebretsen L. High prevalence of overuse injury among iron-distance triathletes. Br. J. Sports Med. 2013; 47:857–61.
[6] Kienstra CM, Asken TR, Garcia JD, Lara V, Best TM. Triathlon injuries: Transitioning from prevalence to prediction and prevention. Current sports medicine reports. 2017 Nov 1;16(6):397-403.
[7] Laursen PB. Long distance triathlon: demands, preparation and performance. Hum. Sport Exerc. 2011; 6(2): 247-263.
[8] Abbiss CR, Quod MJ, Martin DT, Netto KJ, Nosaka K, Lee H, Surriano R, Bishop D, Laursen PB. Dynamic pacing strategies during the cycle phase of an Ironman triathlon. Medicine & Science in Sports & Exercise. 2006 Apr 1;38(4):726-34.
[9] Angehrn N, Rust CA, Nikolaidis PT, Rosemann T, Knechtle B. Positive pacing in elite IRONMAN triathletes. Chin. J. Physiol. 2016 Dec 31;59:305-14.
