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The master female triathlete
Abstract
The world of triathlon has expanded to include all ages and both sexes. One of the largest growing age groups is the master female athlete. It is important for the physical therapist to understand the special needs of this population in order to adequately care for master female athletes so they can participate at a high level and injury-free. Biology of aging, injury prevention and a suggested training program are presented in this Masterclass article.
... In addition to altering the overall strength and stability of the knee, the Q-angle can also impact the ankle joint. The ankle joint is the point where the tibia, fibula, and talus bones meet [14]. The lateral border of the joint is formed by the articular facet of the lateral malleolus, while the articular facet of the medial malleolus forms the medial border [14]. ...
... The ankle joint is the point where the tibia, fibula, and talus bones meet [14]. The lateral border of the joint is formed by the articular facet of the lateral malleolus, while the articular facet of the medial malleolus forms the medial border [14]. The superior portion of the ankle joint is formed by the inferior articular surface of the tibia and the superior margin of the talus. ...
... The Q-angle influences one sex more than the other and is more significant for certain sports than others. Every sport uses the Q-angle, but postpuberty female athletes' athletic performance is where it really stands out [14]. Until puberty, male and female adolescents have similar average Q-angles [26]. ...
The quadriceps angle, knowns as the Q-angle, is an anatomical feature of the human body that is still largely unknown and unstudied despite its initial discovery in the 1950s. The strength disparities between male and female athletes are largely determined by the Q-angle. In spite of a growing number of women participating in sports such as track, tennis, soccer, gymnastics, basketball, volleyball, swimming, and softball, studies investigating injuries in this group are scanty. Even though the Q-angle has been the subject of many studies carried out all over the world, a review of the literature regarding its effects on health and injury risk in female athletes has not yet been completed. The aim of this review is to examine the crucial role of the Q-angle in the biomechanics of the knee joint and its effect on performance and injury risk, particularly in female athletes. Furthermore, we highlight the greater likelihood of knee-related injuries seen in female athletes being caused by the Q-angle. Athletes, coaches, healthcare professionals, and athletic trainers can better comprehend and prepare for the benefits and drawbacks resulting from the Q-angle by familiarizing themselves with the research presented in this review.
... 8 Since VO 2max is dependent on cardiac output and oxygen exchange between the arterial and venous systems, lowered VO 2max reflects reduced efficiency of the pumping heart, stiffness in the vascular system, and declining lung capacity. 9 This can reduce available blood volume to exercising muscles. Nevertheless, high levels of consistent exercise can decrease the age-related decline in VO 2max by nearly 50%. 5 By combining training volume with moderate and vigorous training intensities, older female athletes can maximize their VO 2max , cardiovascular health, and running performance. ...
... Decreased BMD combined with forces generated from each foot contact during running (loading rate) may present increased risk of stress fracture in older female athletes who participate in long-distance running. 9 In fact, older runners endure greater vertical loading rates and initial ground reaction forces, which have been associated with tibial stress fractures. 24 Evidence supports utilizing heavy resistance training to mitigate age-related declines in muscle mass and muscular strength and power and to maintain or increase BMD, thus, positively affecting bone health in older females. ...
... 10 Aging also results in reduced tolerance of musculoskeletal connective tissues, including tendons and ligaments, to physical stress. 9,17 Mature bodily tissues show reduced metabolic rates, greater crosslinkage of collagen fibers, progressively declining elasticity, increased rigidity, and lower tensile strength, which leads to increased stiffness, decreased flexibility, and less workload tolerance in older athletes. 17,27 Flexibility is estimated to decline 6% in every decade of life after 50 years of age. ...
When approaching menopause, female runners may be unaware of the physiological changes that can affect the body and its ability to participate and perform in recreational and competitive sports. Nearly half of recreational female runners are of menopausal age, and health care professionals, including physical therapists, should be aware of the cardiovascular, musculoskeletal, neuromus-cular, and endocrine changes that come with age and menopause to appropriately advise and care for this growing group of female athletes. A comprehensive, integrated approach to training during this time in a woman's life is warranted. By integrating lifestyle behaviors such as sleep, recovery, and nutrition with aerobic and strength training elements, the older female runner is more likely to be able to participate and perform in sport at recreational and competitive levels. Enabling the female athlete to continue running through menopause provides numerous benefits including physical health, psychological wellness, social engagement, and personal accomplishment. This article summarizes the natural changes that occur with aging and menopause and guides physical therapists in developing a comprehensive program of focused training, planned nutrition, and ample recovery for female runners. Supplemental Digital Content video abstract available at:
... VȮ 2 max is dependent on cardiac output (heart rate 3 stroke volume) and the exchange of oxygen between the arterial and venous systems. The decline in VȮ 2 max reflects reduced efficiency of the pumping heart, stiffness in the vascular system, and declining lung capacity (24). A lesser amount of blood pumped out by the heart results in less blood available for exercising muscles. ...
... Masters female athletes will benefit from a combination of high-intensity and high-volume cardiovascular training to decrease age-related declines in HRmax and maximal oxygen consumption. Utilization of a warm-up period focusing on increasing metabolism and blood flow is recommended to prepare the body for exertion (24). ...
... Loss of BMD and lean mass presents greater risk of osteopenia, sarcopenia, and eventually osteoporosis. Masters female athletes participating in long-distance running may be at increased risk of stress fracture because of increased loading rates combined with decreased bone mineral density (24). Evidence suggests that resistance training with higher loading forces has a positive effect on bone health in older women by maintaining or increasing BMD (42). ...
Female participation in sport as a masters athlete has grown considerably in recent years. Functional losses and physiological changes in the cardiovascular, musculoskeletal, and endocrine systems that occur with female aging require recognition and thoughtful exercise prescription. In working with this population, the strength and conditioning professional should be able to recognize the biology of aging, factors affecting recovery and performance, and application of appropriate training parameters to keep the female athlete in their sport while mitigating the effects of aging and maximizing performance. This special populations article outlines key age-related changes in the female athlete and presents comprehensive, practical training guidelines for this growing population.
... To the best of our knowledge, there have been no studies investigating the efficacy of ST programs to prevent injuries in LD triathletes; however, ST programs have been shown to reduce overuse sporting injuries by almost half in a variety of other sports (54). The implementation of ST has however been recommended for masters ($40 years old) and female triathletes to decrease injury risk (57). To assist in preventing the high occurrence of injury in LD triathletes, ST programs should consider including some specific injury prevention exercises. ...
... In addition, ST can be incorporated to help improve biomechanics and absorption of ground reaction forces to help decrease the high occurrence of stress fractures in triathletes (57,68). These injury prevention-based exercises may be included as an "activation" or "assistance" exercise which can be completed before heavy STand act as a dynamic warm-up. ...
Concurrent training, commonly acknowledged as a training method where strength and endurance training are completed complementary to each other, is a strategy often implemented in endurance cyclists' and runners' programs to improve physiological determinants of success such as exercise economy. Although concurrent training methods and strategies have been examined to a large extent in endurance cyclists and runners, literature examining optimal concurrent training methods to improve physiological variables in long-distance triathletes is minimal, leaving optimal programming relatively unknown. This practical applications paper identifies and outlines current concepts and considerations regarding concurrent training for long-distance triathletes including mechanisms contributing to improved performance, muscle and movement patterns used, exercise selection, load, velocity of movement, scheduling, frequency, and duration of training. Common misconceptions related to concurrent training are also identified and practical considerations for the application of concurrent training for coaches, athletes, and other professionals to improve all 3 disciplines of triathlon are discussed.
... With the proper training and techniques for all facets of triathlons including endurance, strength training, flexibility, and recovery, a triathlete has physical abilities which exceed those of their age-matched peers that do not exercise. The name 'Master triathletes' are reserved for triathletes aged 40 years and older (Loudon 2016). At 30%, members age 40-49 comprised the largest growing group of triathletes from the governing body, USA Triathlon, in 2015 (USA Triathlon 2016). ...
Demonstrating health disparities related to race, age, and gender, older Black women (BW) are the most sedentary demographic group in the United States. Increasing PA in mid-life is important, as it improves health as BW age into their later years. Advancing our understanding of the exercise motives of BW triathletes presents a “reverse engineering” opportunity to identify motives that could influence sedentary mid-life BW to increase their activity. The purposes of this study were to: (a) utilize an innovative survey transformation method to adapt a measure developed primarily in Caucasian males, i.e., the Motivations of Marathoners Scale for Triathletes (MOMS-T) into a qualitative interview guide for use with BW triathletes; (b) use this interview guide to identify culturally based motives for triathlon participation among BW not previously addressed by the MOMS-T and; (c) interpret the novel motivational domains of the MOMS-T discovered, in order to gain understanding and influence subsequent interventions. Purposive sampling was used to select 12 interview participants from 121 self-identified Black female US residents aged ≥36 years with recent experience completing or training for a triathlon. The interviews identified four culturally based themes, including improving body composition to become “more lean”, physical attractiveness, triathlete family, and camaraderie. These novel themes were related to existing MOMS-T scales, but the current MOMS-T questions did not illuminate their culturally distinct aspects. The process of survey transformation provides a viable approach to identify important culturally based characteristics and to adapt surveys to cultural minority populations, particularly when study resources are limited.
An increasing life expectancy has impacted our lives positively, but, at the same time, it has become a challenge to live longer, physically and mentally healthy. This biological event has triggered elderly athletes to make their athletic careers longer. In addition, it has also played an essential role in stimulating the elderly to practice sports. A clear sign is that the number of master competitions has grown exponentially in the last decades, as well as the increasing interest of sponsors and participants independently of the modality of practiced sport. In sports, aging may affect individuals in three different scenarios: the elderly and sedentary adults who have become regular sports practitioners or even real athletes, athletes who are getting older, and master athletes. The chapter aims to discuss metabolic and physiological changes of aging, potential red flags in elderly athletes, predisposing injury risk in the elderly athlete, main clinical complaints of elderly athletes, and managing the harmful effects of aging.
Introdução: A natação é um esporte que oferece inúmeros benefícios, entretanto, o excesso da prática pode ser um risco para o sistema musculoesquelético, principalmente entre os nadadores profissionais. O papel da fisioterapia traumato-ortopédica é revisar criticamente o programa de treinamento e tomar conhecimento do que se espera dos atletas. Ele deve dar sugestões e fazer recomendações em benefício da saúde. A atuação do fisioterapeuta na equipe interdisciplinar pode contribuir para uma melhor organização de serviços e consequentemente, melhor atendimento. Objetivo: Investigar a relevância da fisioterapia traumato-ortopédica nos atletas de natação. Métodos: Trata-se de uma revisão integrativa da literatura. O levantamento bibliográfico ocorreu durante o mês de junho de 2022 nas seguintes bases de dados: LILACS, MEDLINE e SciELO. Utilizamos combinações dos descritores nos idiomas português, inglês e espanhol: “Fisioterapia”, “Atletas” e “Natação”. Resultados: A partir do levantamento bibliográfico e da análise dos artigos, sete foram selecionados e compuseram a versão final desse estudo. Com base nos dados expostos na pesquisa podemos perceber que o profissional da fisioterapia se demonstra indispensável para os atletas de natação tanto a nível competitivo quanto a nível amador. Conclusão: A fisioterapia se faz fundamental dentro da equipe interdisciplinar que presta serviços aos atletas de natação, pois a atuação está presente em todas as esferas de atenção como na vigilância epidemiológica avaliando possíveis lesões, condutas terapêuticas preventivas, prescrições e adequações de atividades físicas, reabilitação e orientações gerais. Assim mantendo a longevidade na prática.
Like any sport, running is affected by biological development, the body process of maturity and degeneration. Each phase of our lives, childhood, adolescence, and old age plays an essential role in this physiological development—lifetime effect. Therefore, to evaluate the development of sports skills, the sports physician must systematically assess the neurological, cognitive, somatic, and psychological functions before classifying a runner or athlete as a sports talent without considering the individual’s maturation phase. For most runners, the passion for running is born after overcoming their own physical limits for the first time. However, some of them will go beyond, dreaming of new physical challenges and, consequently, developing a trigger to adopt a non-stop behavior of faster-increasing training and running to reach their self-imposed goals—the “perfect” scenario for injuries. It may affect children, adolescents, and elderly runners indistinctly, where lower limb injuries are prevalent. The sports physician should be aware of inadequate running program regarding the volume, intensity, frequency of training, and muscle imbalances. Moreover, injuries prevention should identify runner’s biological body development, physical and psychological stress related to running or other sports practice, and its mental balance status—“Forrest Gump” runner’s behavior syndrome”.
As the world population is aging, there has also been an increase in the older athletic population. Master athletes are older individuals who engage in lifelong regular training and sports at a competitive level. This population is the epitome of health, physical strength, and speed. Master athletes also serve as non-pharmacological models for successful aging and prevention of chronic diseases and disabilities from a public health perspective. When caring for master athletes, clinicians should take into consideration unique characteristics of these individuals including key physiologic changes associated with aging which may impact their training and rehabilitation. In this chapter, we will discuss the age-related changes in the cardiopulmonary, musculoskeletal, and neurological systems which may impact the performance of master athletes. We will focus on the relevant features of master athletes to prevent and manage common injuries among master athletes. Finally, we will discuss sports-specific considerations for master athletes.
Age-related changes in physiology of master triathletes (i.e. >40 years old) result inevitably in a decrease in triathlon performance. The increase in participation of master triathletes in short- and long-distance triathlons over the last decades has been accompanied by an improvement in their performances at a faster rate than their younger counterparts. Age-related declines in triathlon performance depend upon the discipline (swimming, cycling or running), the event duration (short versus long distance), the type of triathlon (road-based versus off-road triathlon) and sex of the participant. Reductions in the maximal oxygen consumption (VO2max), blood lactate threshold and submaximal exercise economy all contribute to the decrease in triathlon performance with advancing age, but VO2max appears to be the parameter that is the most altered by age. Master triathletes may require greater recovery durations between training sessions to allow optimal both physical and psychological recovery. Further studies investigating different training regimes (e.g. concurrent strength and aerobic training, high-intensity interval training), recovery capacities, nutrition habits and psychology of master triathletes are needed to gain better insights on age-related declines in triathlon performance.
It is widely accepted that warming-up prior to exercise is vital for the attainment of optimum performance. Both passive and active warm-up can evoke temperature, metabolic, neural and psychology-related effects, including increased anaerobic metabolism, elevated oxygen uptake kinetics and post-activation potentiation. Passive warm-up can increase body temperature without depleting energy substrate stores, as occurs during the physical activity associated with active warm-up. While the use of passive warm-up alone is not commonplace, the idea of utilizing passive warming techniques to maintain elevated core and muscle temperature throughout the transition phase (the period between completion of the warm-up and the start of the event) is gaining in popularity. Active warm-up induces greater metabolic changes, leading to increased preparedness for a subsequent exercise task. Until recently, only modest scientific evidence was available supporting the effectiveness of pre-competition warm-ups, with early studies often containing relatively few participants and focusing mostly on physiological rather than performance-related changes. External issues faced by athletes pre-competition, including access to equipment and the length of the transition/marshalling phase, have also frequently been overlooked. Consequently, warm-up strategies have continued to develop largely on a trial-and-error basis, utilizing coach and athlete experiences rather than scientific evidence. However, over the past decade or so, new research has emerged, providing greater insight into how and why warm-up influences subsequent performance. This review identifies potential physiological mechanisms underpinning warm-ups and how they can affect subsequent exercise performance, and provides recommendations for warm-up strategy design for specific individual and team sports.
A better understanding of current swimming warm-up strategies is needed to improve their effectiveness. The purpose of this study was to describe current pre-competition warm-up practices and identify contemporary issues faced by elite swimming coaches during competition. Forty-six state-international level swimming coaches provided information via a questionnaire on their prescription of volume, intensity and recovery within their pool and dryland-based competition warm-ups, and challenges faced during the final stages of event preparation. Coaches identified four key objectives of the pre-competition warm-up: physiological (elevate body temperature/muscle activation), kinesthetic (tactile preparation, increase "feel" of the water), tactical (race-pace rehearsal) and mental (improve focus, reduce anxiety). Pool warm-up volume ranged from ∼1300-2100 m, beginning with 400-1000 m of continuous, low-intensity (∼50-70% of perceived maximal exertion) swimming, followed by 200-600 m of stroke drills and 1-2 sets (100-400 m in length) of increasing intensity (∼60-90%) swimming, concluding with 3-4 race or near race-pace efforts (25-100 m; ∼90-100%) and 100-400 m easy swimming. Dryland-based warm-up exercises, involving stretch cords and skipping, were also commonly prescribed. Coaches preferred swimmers complete their warm-up 20-30 min prior to race start. Lengthy marshalling periods (15-20+ min) and the time required to don racing suits (>10 min) were identified as complicating issues. Coaches believed the pool warm-up affords athletes the opportunity to gain a tactile "feel" for the water and surrounding pool environment. The combination of dryland-based activation exercises followed by pool-based warm-up routines appears to be the preferred approach taken by elite swimming coaches preparing their athletes for competition.
Objectives:
Recent studies have identified rates of injuries in young elite athletes during major athletic events. However, no such data exist on master athletes. The aim of this study was to assess incidence and types of injuries during the 2012 European Veteran Athletics Championships as a function of age, performance and athletic discipline.
Methods:
Report forms were used to identify injured athletes and injury types. Analysis included age (grouped in five-year bands beginning at age 35 years), athletic event, and age-graded performance.
Results:
Of the 3154 athletes (53.2 years (SD 12.3)) that participated in the championships (1004 (31.8%) women, 2150 (68.2%) men), 76 were registered as injured; 2.8% of the female (29), 2.2% of the male (47) athletes. There were no fractures. One injury required operative treatment (Achilles tendon rupture). Injury rates were significantly higher in the sprint/middle distance/jumps than the throws, long distance and decathlon/heptathlon groups (X(2) (3)=16.187, P=0.001). There was no significant interrelationship with age (X(2) (12)=6.495, P=0.889) or age-graded performance (X(2) (3)=3.563, P=0.313).
Conclusions:
The results suggest that healthy master athletes have a low risk of injury that does not increase with age or performance.
A high number of recreational runners sustain a running-related injury each year. To reduce injury risk, alterations in running form have been suggested. One simple strategy for running stride frequency or length has been commonly advocated.
To characterize how running mechanics change when stride frequency and length are manipulated.
In January 2012, a comprehensive search of PubMed, CINAHL Plus, SPORTDiscus, PEDro, and Cochrane was performed independently by 2 reviewers. A second search of the databases was repeated in June 2012 to ensure that no additional studies met the criteria after the initial search.
Inclusion criteria for studies were an independent variable including manipulation of stride frequency or length at a constant speed with outcome measures of running kinematics or kinetics.
Systematic review.
Level 3.
Two reviewers independently appraised each article using a modified version of the Quality Index, designed for assessing bias of nonrandomized studies.
Ten studies met the criteria for this review. There was consistent evidence that increased stride rate resulted in decreased center of mass vertical excursion, ground reaction force, shock attenuation, and energy absorbed at the hip, knee, and ankle joints. All but 1 study had a limited number of participants, with several methodological differences existing among studies (eg, overground and treadmill running, duration of test conditions). Although speed was held constant during testing, it was individually self-selected or fixed. Most studies used only male participants.
Despite procedural differences among studies, an increased stride rate (reduced stride length) appears to reduce the magnitude of several key biomechanical factors associated with running injuries.
Shoulder impingement is a progressive orthopedic condition that occurs as a result of altered biomechanics and/or structural abnormalities. An effective nonoperative treatment for impingement syndrome is aimed at addressing the underlying causative factor or factors that are identified after a complete and thorough evaluation. The clinician devises an effective rehabilitation program to regain full glenohumeral range of motion, reestablish dynamic rotator cuff stability, and implement a progression of resistive exercises to fully restore strength and local muscular endurance in the rotator cuff and scapular stabilizers. The clinician can introduce stresses and forces via sport-specific drills and functional activities to allow a return to activity.
We aimed to investigate the effects of different warm-up (WUP) intensities on 10 min of subsequent intermittent-sprint running performance. Eleven male, team-sport players performed four trials in a randomized, cross-over design, consisting of an intermittent-sprint protocol (15 × 20-m sprints) that followed either no-WUP or one of three 10-min WUP trials that varied in intensity. Warm-up intensities were performed at either (1) half the difference between anaerobic threshold (AT) and lactate threshold (LT) [(AT-LT)/2] below the LT = WUP 1; (2) midway between LT and AT level = WUP 2; (3) [(AT-LT)/2] above AT = WUP 3. Sprint times were fastest following WUP 3, compared with all other trials, for sprints 1-9 and 14, as well as for total accumulated sprints, with these results supported by moderate to large effect size (ES; range: d = -0.50 to -1.06) and "possible" to "almost certain" benefits. Warm-up 3 resulted in faster intermittent-sprint running performance compared with lower intensity WUPs and no WUP for the first 6 min of sprinting, with accumulated sprints for the entire 10 min protocol also being faster after WUP 3. This information may be pertinent to coaches of team-sport games with respect to player substitutions.
The influences of sex and age upon endurance performance have previously been documented for both running and swimming. A number of recent studies have investigated how sex and age influence triathlon performance, a sport that combines three disciplines (swimming, cycling and running), with competitions commonly lasting between 2 (short distance: 1.5-km swim, 40-km cycle and 10-km run) and 8 h (Ironman distance: 3.8-km swim, 180-km cycle and 42-km run) for elite triathletes. Age and sex influences upon performance have also been investigated for ultra-triathlons, with distances corresponding to several Ironman distances and lasting several days, and for off-road triathlons combining swimming, mountain biking and trail running. Triathlon represents an intriguing alternative model for analysing the effects of age and sex upon endurance and ultra-endurance (>6 h) performance because sex differences and age-related declines in performance can be analysed in the same individuals across the three separate disciplines. The relative participation of both females and masters athletes (age >40 years) in triathlon has increased consistently over the past 25 years. Sex differences in triathlon performance are also known to differ between the modes of locomotion adopted (swimming, cycling or running) for both elite and non-elite triathletes. Generally, time differences between sexes in swimming have been shown to be smaller on average than during cycling and running. Both physiological and morphological factors contribute to explaining these findings. Performance density (i.e. the time difference between the winner and tenth-placed competitor) has progressively improved (time differences have decreased) for international races over the past two decades for both males and females, with performance density now very similar for both sexes. For age-group triathletes, sex differences in total triathlon performance time increases with age. However, the possible difference in age-related changes in the physiological determinants of endurance and ultra-endurance performances between males and females needs further investigation. Non-physiological factors such as low rates of participation of older female triathletes may also contribute to the greater age-related decline in triathlon performance shown by females. Total triathlon performance has been shown to decrease in a curvilinear manner with advancing age. However, when triathlon performance is broken down into its three disciplines, there is a smaller age-related decline in cycling performance than in running and swimming performances. Age-associated changes in triathlon performance are also related to the total duration of triathlon races. The magnitude of the declines in cycling and running performances with advancing age for short triathlons are less pronounced than for longer Ironman-distance races. Triathlon distance is also important when considering how age affects the rate of the decline in performance. Off-road triathlon performances display greater decrements with age than road-based triathlons, suggesting that the type of discipline (road vs. mountain bike cycling and road vs. trail running) is an important factor in age-associated changes in triathlon performance. Finally, masters triathletes have shown relative improvements in their performances across the three triathlon disciplines and total triathlon event times during Ironman races over the past three decades. This raises an important issue as to whether older male and female triathletes have yet reached their performance limits during Ironman triathlons.
Much recent attention has been given to the compatibility of combined aerobic and anaerobic training modalities. However few of these studies have reported data related to well-trained runners, which is a potential limitation. Therefore, due to the limited evidence available for this population, the main aim was to determine which mode of concurrent strength-endurance training might be the most effective at improving running performance in highly-trained runners. Eighteen well-trained male runners (age 23.7± 1.2 yr) with a maximal oxygen consumption (VO2max) higher than 65 mL·kg·min were randomly assigned into one of the three groups: Endurance-only Group (EG; n=6), who continued their usual training, which included general strength training with Thera-band latex-free exercise bands and endurance training; Strength Group (SG; n=6) who performed combined resistance and plyometric exercises and endurance training; Endurance-Strength Group (ESG; n=6) who performed endurance-strength training with loads of 40% and endurance training.. The study comprised 12 weeks of training in which runners trained 8 times a week (6 endurance sessions and 2 strength sessions) and 5 weeks of detraining. The subjects were tested on three different occasions (counter movement jump height, hopping test average height, one-repetition-maximum, running economy, VO2max, maximal heart rate (HRmax), peak velocity, rating of perceived exertion and 3-km time trial were measured). Findings revealed significant time x group interaction effects for all almost tests (p <0.05). We can conclude that concurrent training (CT) for both SG and ESG groups led to improved maximal strength, running economy and peak velocity with no significant effects on the VO2 kinetics pattern. The SG group also seems to show improvements in 3-km time trial tests.
Competitive swimming has become an increasingly popular sport in the United States. In 2007, more than 250 000 competitive swimmers were registered with USA Swimming, the national governing body. The average competitive swimmer swims approximately 60 000 to 80 000 m per week. With a typical count of 8 to 10 strokes per 25-m lap, each shoulder performs 30 000 rotations each week. This places tremendous stress on the shoulder girdle musculature and glenohumeral joint, and it is why shoulder pain is the most frequent musculoskeletal complaint among competitive swimmers.
Articles were obtained through a variety of medical search sources, including Medline, Google Scholar, and review articles from 1980 through January 2010.
The most common cause of shoulder pain in swimmers is supraspinatus tendinopathy. Glenohumeral instability and labral tears have also been reported, but a paucity of information remains regarding prevalence and treatment in swimmers.
Because of the great number of stroke repetitions and force generated through the upper extremity, the shoulder is uniquely vulnerable to injury in the competitive swimmer. Comprehensive evaluation should include the entire kinetic chain, including trunk strength and core stability.
Despite of the growth of ultra-endurance sports events (of duration >6 h) over the previous few decades, the age-related declines in ultra-endurance performance have drawn little attention. The aim of the study was to analyse the changes in participation and performance trends of older (>40 years of age) triathletes between 1986 and 2010 at the Hawaii Ironman triathlon consisting of 3.8 km swimming, 180 km cycling and 42 km running. Swimming, cycling, running and total times of the best male and female triathletes between 18 and 69 years of age who competed in the Hawaii Ironman triathlon were analysed. The relative participation of master triathletes increased during the 1986-2010 period, while the participation of triathletes younger than 40 years of age decreased. Linear regression showed that males older than 44 years and females older than 40 years significantly improved their performances in the three disciplines and in the total time taken to complete the race. Gender differences in total time performance significantly decreased in the same time period for all age groups between the 40-44 and 55-59 years ones. The reasons for these relative improvements of Ironman athlete performances in older age groups remain, however, unknown. Further studies investigating training regimes, competition experience or sociodemographic factors are needed to gain better insights into the phenomenon of increasing participation and improvement of ultra-endurance performance with advancing age.
An athlete's carbohydrate intake can be judged by whether total daily intake and the timing of consumption in relation to exercise maintain adequate carbohydrate substrate for the muscle and central nervous system ("high carbohydrate availability") or whether carbohydrate fuel sources are limiting for the daily exercise programme ("low carbohydrate availability"). Carbohydrate availability is increased by consuming carbohydrate in the hours or days prior to the session, intake during exercise, and refuelling during recovery between sessions. This is important for the competition setting or for high-intensity training where optimal performance is desired. Carbohydrate intake during exercise should be scaled according to the characteristics of the event. During sustained high-intensity sports lasting ~1 h, small amounts of carbohydrate, including even mouth-rinsing, enhance performance via central nervous system effects. While 30-60 g · h(-1) is an appropriate target for sports of longer duration, events >2.5 h may benefit from higher intakes of up to 90 g · h(-1). Products containing special blends of different carbohydrates may maximize absorption of carbohydrate at such high rates. In real life, athletes undertake training sessions with varying carbohydrate availability. Whether implementing additional "train-low" strategies to increase the training adaptation leads to enhanced performance in well-trained individuals is unclear.
Incorrect bicycle configuration may predispose athletes to injury and reduce their cycling performance. There is disagreement within scientific and coaching communities regarding optimal configuration of bicycles for athletes. This review summarizes literature on methods for determining bicycle saddle height and the effects of bicycle saddle height on measures of cycling performance and lower limb injury risk. Peer-reviewed journals, books, theses and conference proceedings published since 1960 were searched using MEDLINE, Scopus, ISI Web of Knowledge, EBSCO and Google Scholar databases, resulting in 62 references being reviewed. Keywords searched included 'body positioning', 'saddle', 'posture, 'cycling' and 'injury'. The review revealed that methods for determining optimal saddle height are varied and not well established, and have been based on relationships between saddle height and lower limb length (Hamley and Thomas, trochanteric length, length from ischial tuberosity to floor, LeMond, heel methods) or a reference range of knee joint flexion. There is limited information on the effects of saddle height on lower limb injury risk (lower limb kinematics, knee joint forces and moments and muscle mechanics), but more information on the effects of saddle height on cycling performance (performance time, energy expenditure/oxygen uptake, power output, pedal force application). Increasing saddle height can cause increased shortening of the vastii muscle group, but no change in hamstring length. Length and velocity of contraction in the soleus seems to be more affected by saddle height than that in the gastrocnemius. The majority of evidence suggested that a 5% change in saddle height affected knee joint kinematics by 35% and moments by 16%. Patellofemoral compressive force seems to be inversely related to saddle height but the effects on tibiofemoral forces are uncertain. Changes of less than 4% in trochanteric length do not seem to affect injury risk or performance. The main limitations from the reported studies are that different methods have been employed for determining saddle height, small sample sizes have been used, cyclists with low levels of expertise have mostly been evaluated and different outcome variables have been measured. Given that the occurrence of overuse knee joint pain is 50% in cyclists, future studies may focus on how saddle height can be optimized to improve cycling performance and reduce knee joint forces to reduce lower limb injury risk. On the basis of the conflicting evidence on the effects of saddle height changes on performance and lower limb injury risk in cycling, we suggest the saddle height may be set using the knee flexion angle method (25-30°) to reduce the risk of knee injuries and to minimize oxygen uptake.
It is not clear how noncyclists control joint power and kinematics in different mechanical setups (saddle height, workload, and pedaling cadence). Joint mechanical work contribution and kinematics analysis could improve our comprehension of the coordinative pattern of noncyclists and provide evidence for bicycle setup to prevent injury.
To compare joint mechanical work distribution and kinematics at different saddle heights, workloads, and pedaling cadences.
Quantitative experimental research based on repeated measures.
Research laboratory.
9 healthy male participants 22 to 36 years old without competitive cycling experience.
Cycling on an ergometer in the following setups: 3 saddle heights (reference, 100% of trochanteric height; high, +3 cm; and low, -3 cm), 2 pedaling cadences (40 and 70 rpm), and 3 workloads (0, 5, and 10 N of braking force).
Joint kinematics, joint mechanical work, and mechanical work contribution of the joints.
There was an increased contribution of the ankle joint (P=.04) to the total mechanical work with increasing saddle height (from low to high) and pedaling cadence (from 40 to 70 rpm, P<.01). Knee work contribution increased when saddle height was changed from high to low (P<.01). Ankle-, knee-, and hip-joint kinematics were affected by saddle height changes (P<.01).
At the high saddle position it could be inferred that the ankle joint compensated for the reduced knee-joint work contribution, which was probably effective for minimizing soft-tissue damage in the knee joint (eg, anterior cruciate ligament and patellofemoral cartilage). The increase in ankle work contribution and changes in joint kinematics associated with changes in pedaling cadence have been suggested to indicate poor pedaling-movement skill.
This study describes the decline in performance with age during Olympic triathlon Age Groups World Championships among the different locomotion modes. Mean performance of top 10 performers were analyzed for each group of age using the exponential model proposed by Baker, Tang, and Turner (20031.
Baker , A. B. ,
Tang , Y. Q. , &
Turner , M. J. ( 2003 ). Percentage decline in masters superathlete track and field performance with aging . Experimental Aging Research , 29 , 47 – 65 . [Taylor & Francis Online], [PubMed], [Web of Science ®], [CSA]View all references, Experimental Aging Research, 29, 47–65). Comparison in performance decline was done between locomotion modes. Decline in performance in triathlon as a function of age follows an exponential model. A significant interaction effect between age and locomotion mode was observed on performance values. In swimming, a significant decrease was observed close to 5% per year after 45 years. Decline in performance was less pronounced in cycling until 60 years. Analysis of the effect of age in the different locomotion modes of a triathlon could provide information for maintaining quality of life with aging.
Exercise has been shown to improve many health outcomes and well-being of people of all ages. Long-term studies in older adults are needed to confirm disability and survival benefits of exercise.
Annual self-administered questionnaires were sent to 538 members of a nationwide running club and 423 healthy controls from northern California who were 50 years and older beginning in 1984. Data included running and exercise frequency, body mass index, and disability assessed by the Health Assessment Questionnaire Disability Index (HAQ-DI; scored from 0 [no difficulty] to 3 [unable to perform]) through 2005. A total of 284 runners and 156 controls completed the 21-year follow-up. Causes of death through 2003 were ascertained using the National Death Index. Multivariate regression techniques compared groups on disability and mortality.
At baseline, runners were younger, leaner, and less likely to smoke compared with controls. The mean (SD) HAQ-DI score was higher for controls than for runners at all time points and increased with age in both groups, but to a lesser degree in runners (0.17 [0.34]) than in controls (0.36 [0.55]) (P < .001). Multivariate analyses showed that runners had a significantly lower risk of an HAQ-DI score of 0.5 (hazard ratio, 0.62; 95% confidence interval, 0.46-0.84). At 19 years, 15% of runners had died compared with 34% of controls. After adjustment for covariates, runners demonstrated a survival benefit (hazard ratio, 0.61; 95% confidence interval, 0.45-0.82). Disability and survival curves continued to diverge between groups after the 21-year follow-up as participants approached their ninth decade of life.
Vigorous exercise (running) at middle and older ages is associated with reduced disability in later life and a notable survival advantage.
The purpose of this study was to determine whether muscle metabolic capacity was inversely related to age after adjusting for physical activity in sedentary premenopausal women. Eighty-three women (ages 23-47 yr) had their free-living, activity-related energy expenditure evaluated with doubly labeled water procedures, and room calorimeter determined sleeping energy expenditure. Maximum O(2) uptake and strength were evaluated in all subjects, whereas 31P-magnetic resonance spectroscopy determined metabolic economy during maximal exercise, and muscle biopsy maximal enzyme activity was evaluated in subsets of the sample (48 and 18 subjects, respectively). Age was significantly related to whole body treadmill endurance time (r = -0.32), plantar flexion strength (r = -0.29), maximum O(2) uptake (r = -0.27), (31)P-magnetic resonance spectroscopy ADP recovery rate (r = -0.44), and anaerobic glycolytic capacity (r = -0.37), and muscle biopsy citrate synthase activity (r = -0.48), glyceraldehyde-3-phosphate dehydrogenase (r = -0.54), phosphofructokinase (r = -0.62), and phosphorylase (r = -0.58) activity even after adjusting for activity-related energy expenditure. These data suggest that, in sedentary premenopausal women, both oxidative and glycolytic muscle capacity decrease with age even when physical activity is taken into account.
We followed up swimming performance times of 321 women and 319 men who participated in the US Masters Swimming Championships over a 12-yr period. All swimmers placed in the top 10 in their age group over 3 yr (mean = 5 yr). A random coefficients model for repeated measures was used to derive a line of best fit from a group of regression lines for each subject. Both 50- and 1,500-m swimming performance declined modestly until approximately 70 yr of age, where a more rapid decline was observed in both men and women. Compared with 1,500-m swimming, the 50-m freestyle declined more modestly and slowly with age. The rate and magnitude of declines in swimming performance with age were greater in women than in men in 50-m freestyle; such sex-related differences were not observed in 1,500-m freestyle. Overall, the variability along a population regression line increased markedly with advancing age. The present longitudinal findings indicate that 1) swimming performance declines progressively until age 70, where the decrease becomes quadratic; 2) the rates of the decline in swimming performance with age are greater in a long-duration than in a short-duration event, suggesting a relatively smaller loss of anaerobic muscular power with age compared with cardiovascular endurance; 3) the age-related rates of decline are greater in women than in men only in a short-duration event; and 4) the variability of the age-related decline in performance increases markedly with advancing age.
Descriptive correlational investigation.
To assess the incidence of, and potential risk factors associated with, overuse injury in triathlon.
The sport of triathlon is rapidly increasing in popularity with a concomitant rise in the prevalence of injuries sustained by triathletes.
The training and injury patterns of 131 triathletes were surveyed over a 10-week prospective period during the triathlon competition season. A complementary retrospective 6-month analysis of training history and prior overuse injuries was conducted.
Fifty percent of triathletes sustained an injury in the 6-month preseason at an injury exposure rate of 2.5 per 1000 training hours. Thirty-seven percent were injured during the 10-week competition season at an injury exposure rate of 4.6 per 1000 training hours. Overuse accounted for 68% of preseason and 78% of competition season injuries reported. Increased years of triathlon experience, high running mileage, history of previous injury, and inadequate warming-up and cooling-down regimes appeared to have individual associations with injury incidence. When interactions were included in a multiple logistic regression model, increasing years of triathlon experience was the most significant predictor of preseason injury risk and a previous history of injury and high preseason running mileage increased the risk of injury during the competition season.
The results indicate that in assessing triathletes, a full training and competition history is required by the sports clinician for a comprehensive assessment of the factors that may contribute to overuse injury.
Sports-related injuries are a significant health problem within Australia, and constitute a national health priority. There is limited Australian research data available on factors that contribute to triathlon injuries, and in particular on how training patterns relate to injury risk. This study examined the association between training patterns and injury in mostly non-elite triathletes. A cross-sectional survey of 258 triathletes completed a questionnaire that focused on injuries they had sustained during the previous three triathlon seasons. Statistical associations were found between hours of training and sustaining an injury. These associations were U shaped, with those triathletes training at low levels and at high levels more likely to sustain an injury. The results suggest that, for non-elite triathletes, the likelihood of sustaining an injury is least when training for a total of 8 to 10 hrs per week, specifically cycling for five to six hrs and running for three to four hrs weekly. Time spent on swimming training does not appear to affect injury risk. This research is seen as a contribution towards assisting triathletes in the planning of training programs aimed at reducing the risk of injury.
Age-related decline in muscle power may be an early indicator of balance deficits and fall risk, even in nonfrail adults. This study examined the dose-dependent effect of power training on balance performance in healthy older adults.
One hundred twelve community-dwelling healthy older adults (69 +/- 6 years) were randomized to 8-12 weeks of power training at 20% (LOW), 50% (MED), or 80% (HIGH) of maximal strength, or a nontraining control (CON) group. Participants trained twice weekly (five exercises; three sets of eight rapid concentric/slow eccentric repetitions) using pneumatic resistance machines. Balance, muscle performance (strength, power, endurance, contraction velocity), and body composition were measured.
Power training significantly improved balance performance (p =.006) in participants who underwent power training compared to controls. Low intensity power training produced the greatest improvement in balance performance (p =.048). Average contraction velocity at low load (40% one repetition maximum [1RM]) at baseline independently predicted improvement in balance following training (r = -.29, p =.004).
Power training improves balance, particularly using a low load, high velocity regimen, in older adults with initial lower muscle power and slower contraction. Further studies are warranted to define the mechanisms underlying this adaptation, as well as the optimum power training intensity for a range of physiological and clinical outcomes in older adults with varying levels of health status and functional independence.
The purpose of this study was to examine the effects of different modes of stretching within a pre-exercise warm-up on high-speed motor capacities important to soccer performance. Eighteen professional soccer players were tested for countermovement vertical jump, stationary 10-m sprint, flying 20-m sprint, and agility performance after different warm-ups consisting of static stretching, dynamic stretching, or no stretching. There was no significant difference among warm-ups for the vertical jump: mean +/- SD data were 40.4 +/- 4.9 cm (no stretch), 39.4 +/- 4.5 cm (static), and 40.2 +/- 4.5 cm (dynamic). The dynamic-stretch protocol produced significantly faster 10-m sprint times than did the no-stretch protocol: 1.83 +/- 0.08 seconds (no stretch), 1.85 +/- 0.08 seconds (static), and 1.87 +/- 0.09 seconds (dynamic). The dynamic- and static-stretch protocols produced significantly faster flying 20-m sprint times than did the no-stretch protocol: 2.41 +/- 0.13 seconds (no stretch), 2.37 +/- 0.12 seconds (static), and 2.37 +/- 0.13 seconds (dynamic). The dynamic-stretch protocol produced significantly faster agility performance than did both the no-stretch protocol and the static-stretch protocol: 5.20 +/- 0.16 seconds (no stretch), 5.22 +/- 0.18 seconds (static), and 5.14 +/- 0.17 seconds (dynamic). Static stretching does not appear to be detrimental to high-speed performance when included in a warm-up for professional soccer players. However, dynamic stretching during the warm-up was most effective as preparation for subsequent high-speed performance.
The primary purpose of this narrative review was to evaluate the current literature and to provide further insight into the role physical inactivity plays in the development of chronic disease and premature death. We confirm that there is irrefutable evidence of the effectiveness of regular physical activity in the primary and secondary prevention of several chronic diseases (e.g., cardiovascular disease, diabetes, cancer, hypertension, obesity, depression and osteoporosis) and premature death. We also reveal that the current Health Canada physical activity guidelines are sufficient to elicit health benefits, especially in previously sedentary people. There appears to be a linear relation between physical activity and health status, such that a further increase in physical activity and fitness will lead to additional improvements in health status.
Older ('Masters') athletes strive to maintain or even improve upon the performance they achieved at younger ages, but declines in athletic performance are inevitable with ageing. In this review, we describe changes in peak endurance exercise performance with advancing age as well as physiological factors responsible for those changes. Peak endurance performance is maintained until approximately 35 years of age, followed by modest decreases until 50-60 years of age, with progressively steeper declines thereafter. Among the three main physiological determinants of endurance exercise performance (i.e. maximal oxygen consumption , lactate threshold and exercise economy), a progressive reduction in appears to be the primary mechanism associated with declines in endurance performance with age. A reduction in lactate threshold, i.e. the exercise intensity at which blood lactate concentration increases significantly above baseline, also contributes to the reduction in endurance performance with ageing, although this may be secondary to decreases in . In contrast, exercise economy (i.e. metabolic cost of sustained submaximal exercise) does not change with age in endurance-trained adults. Decreases in maximal stroke volume, heart rate and arterio-venous O(2) difference all appear to contribute to the age-related reductions in in endurance-trained athletes. Declines in endurance exercise performance and its physiological determinants with ageing appear to be mediated in large part by a reduction in the intensity (velocity) and volume of the exercise that can be performed during training sessions. Given their impressive peak performance capability and physiological function capacity, Masters athletes remain a fascinating model of 'exceptionally successful ageing' and therefore are highly deserving of our continued scientific attention as physiologists.
Running is one of the most popular leisure sports activities. Next to its beneficial health effects, negative side effects in terms of sports injuries should also be recognised. Given the limitations of the studies it appears that for the average recreational runner, who is steadily training and who participates in a long distance run every now and then, the overall yearly incidence rate for running injuries varies between 37 and 56%. Depending on the specificity of the group of runners concerned (competitive athletes; average recreational joggers; boys and girls) and on different circumstances these rates vary. If incidence is calculated according to exposure of running time the incidence reported in the literature varies from 2.5 to 12.1 injuries per 1000 hours of running. Most running injuries are lower extremity injuries, with a predominance for the knee. About 50 to 75% of all running injuries appear to be overuse injuries due to the constant repetition of the same movement. Recurrence of running injuries is reported in 20 to 70% of the cases. From the epidemiological studies it can be concluded that running injuries lead to a reduction of training or training cessation in about 30 to 90% of all injuries, about 20 to 70% of all injuries lead to medical consultation or medical treatment and 0 to 5% result in absence from work. Aetiological factors associated with running injuries include previous injury, lack of running experience, running to compete and excessive weekly running distance. The association between running injuries and factors such as warm-up and stretching exercises, body height, malalignment, muscular imbalance, restricted range of motion, running frequency, level of performance, stability of running pattern, shoes and inshoe orthoses and running on 1 side of the road remains unclear or is backed by contradicting or scarce research findings. Significantly not associated with running injuries seem age, gender, body mass index, running hills, running on hard surfaces, participation in other sports, time of the year and time of the day. The prevention of sports injuries should focus on changes of behaviour by health education. Health education on running injuries should primarily focus on the importance of complete rehabilitation and the early recognition of symptoms of overuse, and on the provision of training guidelines.
The purpose of this study was to compare the effect of a dynamic warm up (DWU) with a static-stretching warm up (SWU) on selected measures of power and agility. Thirty cadets at the United States Military Academy completed the study (14 women and 16 men, ages 18-24 years). On 3 consecutive days, subjects performed 1 of the 2 warm up routines (DWU or SWU) or performed no warm up (NWU). The 3 warm up protocols lasted 10 minutes each and were counterbalanced to avoid carryover effects. After 1-2 minutes of recovery, subjects performed 3 tests of power or agility. The order of the performance tests (T-shuttle run, underhand medicine ball throw for distance, and 5-step jump) also was counterbalanced. Repeated measures analysis of variance revealed better performance scores after the DWU for all 3 performance tests (p < 0.01), relative to the SWU and NWU. There were no significant differences between the SWU and NWU for the medicine ball throw and the T-shuttle run, but the SWU was associated with better scores on the 5-step jump (p < 0.01). Because the results of this study indicate a relative performance enhancement with the DWU, the utility of warm up routines that use static stretching as a stand-alone activity should be reassessed.
Background
Although running is a popular leisure-time physical activity, little is known about the long-term effects of running on mortality. The dose-response relations between running, as well as the change in running behaviors over time, and mortality remain uncertain.
Objectives
We examined the associations of running with all-cause and cardiovascular mortality risks in 55,137 adults, 18 to 100 years of age (mean age 44 years).
Methods
Running was assessed on a medical history questionnaire by leisure-time activity.
Results
During a mean follow-up of 15 years, 3,413 all-cause and 1,217 cardiovascular deaths occurred. Approximately 24% of adults participated in running in this population. Compared with nonrunners, runners had 30% and 45% lower adjusted risks of all-cause and cardiovascular mortality, respectively, with a 3-year life expectancy benefit. In dose-response analyses, the mortality benefits in runners were similar across quintiles of running time, distance, frequency, amount, and speed, compared with nonrunners. Weekly running even <51 min, <6 miles, 1 to 2 times, <506 metabolic equivalent-minutes, or <6 miles/h was sufficient to reduce risk of mortality, compared with not running. In the analyses of change in running behaviors and mortality, persistent runners had the most significant benefits, with 29% and 50% lower risks of all-cause and cardiovascular mortality, respectively, compared with never-runners.
Conclusions
Running, even 5 to 10 min/day and at slow speeds <6 miles/h, is associated with markedly reduced risks of death from all causes and cardiovascular disease. This study may motivate healthy but sedentary individuals to begin and continue running for substantial and attainable mortality benefits.
Increasing step rate has been shown to elicit changes in joint kinematics and kinetics during running, and has been suggested as a possible rehabilitation strategy for runners with patellofemoral pain. The purpose of this study was to determine how altering step rate affects internal muscle forces and patellofemoral joint loads, and then to determine what kinematic and kinetic factors best predict changes in joint loading.
We recorded whole body kinematics of 30 healthy adults running on an instrumented treadmill at three step rate conditions (90%, 100%, and 110% of preferred step rate). We then used a 3D lower extremity musculoskeletal model to estimate muscle, patellar tendon, and patellofemoral joint forces throughout the running gait cycles. Additionally, linear regression analysis allowed us to ascertain the relative influence of limb posture and external loads on patellofemoral joint force.
Increasing step rate to 110% of preferred reduced peak patellofemoral joint force by 14%. Peak muscle forces were also altered as a result of the increased step rate with hip, knee and ankle extensor forces, and hip abductor forces all reduced in mid-stance. Compared to the 90% step rate condition, there was a concomitant increase in peak rectus femoris and hamstring loads during early and late swing, respectively, at higher step rates. Peak stance phase knee flexion decreased with increasing step rate, and was found to be the most important predictor of the reduction in patellofemoral joint loading.
Increasing step rate is an effective strategy to reduce patellofemoral joint forces and could be effective in modulating biomechanical factors that can contribute to patellofemoral pain.
Current endurance champions are turning in winning performances in their late 30s and 40s. These masters-age athletes present a special challenge to Sport Medicine practitioners who in previous decades have simply advised masters-aged athletes to stop competing to prevent or treat injury. The fact is, many of the physical changes commonly attributed to aging alone are actually due to the rages of sedentary aging. Recently a body of literature emerged which begins to define what we are capable of with chronic high-level exercise and guides masters-age athletes to train and rehab smarter to stay competitive. The factors influencing the relative declines in overall performance in the various sports include both physiological and lifestyle changes. The following review summarizes age and sex-related changes in triathlon performance, the biology of aging as it relates to endurance sport and factors that affect performance in the masters athletes.
Aging is commonly associated with a loss of muscle mass and strength, resulting in falls, functional decline, and the subjective feeling of weakness. Exercise modulates the morbidities of muscle aging. Most studies, however, have examined muscle-loss changes in sedentary aging adults. This leaves the question of whether the changes that are commonly associated with muscle aging reflect the true physiology of muscle aging or whether they reflect disuse atrophy. This study evaluated whether high levels of chronic exercise prevents the loss of lean muscle mass and strength experienced in sedentary aging adults. A cross-section of 40 high-level recreational athletes ("masters athletes") who were aged 40 to 81 years and trained 4 to 5 times per week underwent tests of health/activity, body composition, quadriceps peak torque (PT), and magnetic resonance imaging of bilateral quadriceps. Mid-thigh muscle area, quadriceps area (QA), subcutaneous adipose tissue, and intramuscular adipose tissue were quantified in magnetic resonance imaging using medical image processing, analysis, and visualization software. One-way analysis of variance was used to examine age group differences. Relationships were evaluated using Spearman correlations. Mid-thigh muscle area (P = 0.31) and lean mass (P = 0.15) did not increase with age and were significantly related to retention of mid-thigh muscle area (P < 0.0001). This occurred despite an increase in total body fat percentage (P = 0.003) with age. Mid-thigh muscle area (P = 0.12), QA (P = 0.17), and quadriceps PT did not decline with age. Specific strength (strength per QA) did not decline significantly with age (P = 0.06). As muscle area increased, PT increased significantly (P = 0.008). There was not a significant relationship between intramuscular adipose tissue (P = 0.71) or lean mass (P = 0.4) and PT. This study contradicts the common observation that muscle mass and strength decline as a function of aging alone. Instead, these declines may signal the effect of chronic disuse rather than muscle aging. Evaluation of masters athletes removes disuse as a confounding variable in the study of lower-extremity function and loss of lean muscle mass. This maintenance of muscle mass and strength may decrease or eliminate the falls, functional decline, and loss of independence that are commonly seen in aging adults.
Loss of ovarian function has a profound impact on female skeletal health. Bone mineral density findings from the Study of Women's Health Across the Nation demonstrate an accelerated rate of bone loss during the menopausal transition. The greatest reduction occurs in the year before the final menstrual period and the first 2 years thereafter. Clinical management includes maintenance of adequate dietary calcium and vitamin D intake, attention to modifiable risk factors, and osteoporosis screening. Indications, benefits, and risks of pharmacologic osteoporosis therapy should be assessed individually; there are currently no established guidelines addressing the treatment and prevention of osteoporosis in perimenopausal women.
Aging is associated with a progressive decline of muscle mass, strength, and quality, a condition described as sarcopenia of aging. Despite the significance of skeletal muscle atrophy, the mechanisms responsible for the deterioration of muscle performance are only partially understood. The purpose of this review is to highlight cellular, molecular, and biochemical changes that contribute to age-related muscle dysfunction.
Practitioners who work with elite athletes know that the pressure and considerable rewards involved with success provide a high level of motivation to look for any safe and legal strategy that might enhance performance, even by small margins. Dietary supplements operate in this space, whether they promise a large performance boost or just create the fear that an athlete cannot afford to miss out on what everyone else is using. It is often tempting to overlook the lack of evidence to support the claims made about a supplement on the basis that the stakes are higher for elite athletes; therefore the cost:benefit ratio favours experimentation in the absence of clear proof. Over the past decade, however, we have become aware that the cost of getting it wrong has also escalated for elite athletes. A new hazard related to supplement use has emerged: inadvertent ingestion of substances that are banned under the antidoping codes in place in elite sport, but present in supplement products. In some cases, the level of the presence, or contamination, of banned substances in supplements presents a health hazard for all consumers. In some cases, the concentration may be too small to achieve any health or performance effect but large enough to record an infringement for athletes who submit to doping tests. Newspapers, the internet and Courts of Arbitration in Sport now bear stories of dedicated athletes whose careers have been or are being jeopardised because of the ingestion of a banned substance via a dietary supplement. This problem was first brought to scientific recognition by Hans Geyer and his colleagues from the Centre for Preventive Doping Research in Cologne. The following article provides an update of a recent review by this team.1
In the past years, an increasing number of dietary supplements containing undeclared doping …
the objective of this study was to characterize the biomechanical effects of step rate modification during running on the hip, knee, and ankle joints so as to evaluate a potential strategy to reduce lower extremity loading and risk for injury.
three-dimensional kinematics and kinetics were recorded from 45 healthy recreational runners during treadmill running at constant speed under various step rate conditions (preferred, ± 5%, and ± 10%). We tested our primary hypothesis that a reduction in energy absorption by the lower extremity joints during the loading response would occur, primarily at the knee, when step rate was increased.
less mechanical energy was absorbed at the knee (P < 0.01) during the +5% and +10% step rate conditions, whereas the hip (P < 0.01) absorbed less energy during the +10% condition only. All joints displayed substantially (P < 0.01) more energy absorption when preferred step rate was reduced by 10%. Step length (P < 0.01), center of mass vertical excursion (P < 0.01), braking impulse (P < 0.01), and peak knee flexion angle (P < 0.01) were observed to decrease with increasing step rate. When step rate was increased 10% above preferred, peak hip adduction angle (P < 0.01) and peak hip adduction (P < 0.01) and internal rotation (P < 0.01) moments were found to decrease.
we conclude that subtle increases in step rate can substantially reduce the loading to the hip and knee joints during running and may prove beneficial in the prevention and treatment of common running-related injuries.
A contributing factor to the loss of muscle mass and strength during aging is the reduction in the number of functioning motor units (MU). It has been shown that lifelong physically active older rats have greater numbers of MU compared with age-matched sedentary controls, suggesting that chronic exercise may preserve MU function with advancing age. This has not previously been examined in humans.
Thus, the purpose of this study was to estimate the number of functioning MU in the tibialis anterior of masters runners (approximately 65 yr) and to compare the values with recreationally active young (approximately 25 yr) and healthy age-matched controls (approximately 65 yr).
Decomposition-enhanced spike-triggered averaging was used to collect surface and intramuscular EMG signals during dorsiflexion at 25% of maximum voluntary isometric contraction.
The estimated number of MU did not differ between masters runners and young, but MU number estimates were lower in the old (91 +/- 22 MU) compared with the masters runners (140 +/- 53 MU) and young (150 +/- 43 MU).
These results demonstrate that lifelong high-intensity physical activity could potentially mitigate the loss of MU associated with aging well into the seventh decade of life.
The value of warming-up is a worthy research problem because it is not known whether warming-up benefits, harms, or has no effect on individuals. The purpose of this study was to review the evidence relating to performance improvement using a warm-up. A systematic review and meta-analysis were undertaken. Relevant studies were identified by searching Medline, SPORTDiscus, and PubMed (1966-April 2008). Studies investigating the effects of warming-up on performance improvement in physical activities were included. Studies were included only if the subjects were human and only if the warm-up included activities other than stretching. The quality of included studies was assessed independently by 2 assessors using the Physiotherapy Evidence Database scale. Thirty-two studies, all of high quality (6.5-9 [mean = 7.6] of 10) reported sufficient data (quality score >6) on the effects of warming-up on performance improvement. Warm-up was shown to improve performance in 79% of the criterions examined. This analysis has shown that performance improvements can be demonstrated after completion of adequate warm-up activities, and there is little evidence to suggest that warming-up is detrimental to sports participants. Because there were few well-conducted, randomized, controlled trials undertaken, more of these are needed to further determine the role of warming-up in relation to performance improvement.
The iliotibial band (ITB) has an important role in knee mechanics and tightness can cause patellofemoral maltracking. This study investigated the effects of increasing ITB tension on knee kinematics. Nine fresh-frozen cadaveric knees had the components of the quadriceps loaded with 175 N. A Polaris optical tracking system was used to acquire joint kinematics during extension from 100 degrees to 0 degrees flexion. This was repeated after the following ITB loads: 30, 60 and 90 N. There was no change with 30 N load for patellar translation. On average, at 60 and 90 N, the patella translated laterally by 0.8 and 1.4mm in the mid flexion range compared to the ITB unloaded condition. The patella became more laterally tilted with increasing ITB loads by 0.7 degrees, 1.2 degrees and 1.5 degrees for 30, 60 and 90 N, respectively. There were comparable increases in patellar lateral rotation (distal patella moves laterally) towards the end of the flexion cycle. Increased external rotation of the tibia occurred from early flexion onwards and was maximal between 60 degrees and 75 degrees flexion. The increase was 5.2 degrees, 9.5 degrees and 13 degrees in this range for 30, 60 and 90 N, respectively. Increased tibial abduction with ITB loads was not observed. The combination of increased patellar lateral translation and tilt suggests increased lateral cartilage pressure. Additionally, the increased tibial external rotation would increase the Q angle. The clinical consequences and their relationship to lateral retinacular releases may be examined, now that the effects of a tight ITB are known.
The biophysical determinants related to swimming performance are one of the most attractive topics within swimming science. The aim of this paper was to do an update of the "state of art" about the interplay between performance, energetic and biomechanics in competitive swimming. Throughout the manuscript some recent highlights are described: (i) the relationship between swimmer's segmental kinematics (segmental velocities, stroke length, stroke frequency, stroke index and coordination index) and his center of mass kinematics (swimming velocity and speed fluctuation); (ii) the relationships between energetic (energy expenditure and energy cost) and swimmer's kinematics; and (iii) the prediction of swimming performance derived from above mentioned parameters.
Achilles tendinopathy is commonly reported by athletes involved in activities that include running and jumping. Despite the prevalence of the problem, causative factors in Achilles tendinopathy remain poorly understood.
In Masters track and field athletes, there is no influence of age, gender, weight, height, and impact profile in developing Achilles tendinopathy.
Cross-sectional study; Level of evidence, 3.
During the European Veterans Athletics Championships in Poznań, Poland, in July 2006, 178 athletes (110 men and 68 women; mean age, 54.1 years; range, 35-94 years) were evaluated with the Victorian Institute of Sport Assessment-Achilles (VISA-A) questionnaire. A fully trained orthopaedic surgeon made a diagnosis of Achilles tendinopathy according to clinical criteria.
There was no effect of gender on the presence of Achilles tendinopathy (P = .14). No significant track and field specialty effect upon the frequency of Achilles tendinopathy was found on the VISA-A questionnaire scores (P = .32). Equally, there was no effect of track and field specialty on the VISA-A score (P = .31). No correlation was found between age and VISA-A score (P = .36). There was no statistically significant difference in either prevalence of Achilles tendinopathy or VISA-A score between high-impact and low-impact athletes (P = .19 and P = .31, respectively).
In competing Masters track and field athletes, we did not find any influence of age, gender, weight, height, or impact profile on the development of Achilles tendinopathy. Additional research is required to improve our understanding of the causative factors in Achilles tendinopathy.
The paper addresses the degree to which the attainment of the status as an elite athlete in different sports ameliorates the known age-related losses in skeletal muscle structure and function.
The retrospective design, based on comparisons of published data on former elite and masters athletes and data on control subjects, assessed the degree to which the attainment of elite and masters athlete status ameliorated the known age-related changes in skeletal muscle structure and function.
Institutional.
Elite male athletes.
Participation in selected individual and team sports.
Strength, power, VO2max, and performance.
For elite athletes in all sports, as for the general population, age-related muscle atrophy begins at about 50 years of age. Despite the loss of muscle mass, elite athletes who maintain an active lifestyle age gracefully with few health problems. Conversely, those who lapse into inactivity regress toward general population norms for fitness, weight control, and health problems. Elite athletes in the dual and team sports have careers that rarely extend into their 30s.
Lifelong physical activity does not appear to have any impact on the loss in fiber number. The loss of fibers can be buffered to some degree by hypertrophy of fibers that remain. It is surprising that the performance of elite athletes in all sports appears to be impaired before the onset of the fiber loss. Even with major losses in physical capacity and muscle mass, the performance of elite and masters athletes is remarkable.
The objective of this study was to compare the three-dimensional lower extremity running kinematics of young adult runners and elderly runners. Seventeen elderly adults (age 67-73 years) and 17 young adults (age 26-36 years) ran at 3.1 m x s(-1) on a treadmill while the movements of the lower extremity during the stance phase were recorded at 120 Hz using three-dimensional video. The three-dimensional kinematics of the lower limb segments and of the ankle and knee joints were determined, and selected variables were calculated to describe the movement. Our results suggest that elderly runners have a different movement pattern of the lower extremity from that of young adults during the stance phase of running. Compared with the young adults, the elderly runners had a substantial decrease in stride length (1.97 vs. 2.23 m; P = 0.01), an increase in stride frequency (1.58 vs. 1.37 Hz; P = 0.002), less knee flexion/extension range of motion (26 vs. 33 degrees ; P = 0.002), less tibial internal/external rotation range of motion (9 vs. 12 degrees ; P < 0.001), larger external rotation angle of the foot segment (toe-out angle) at the heel strike (-5.8 vs. -1.0 degrees ; P = 0.009), and greater asynchronies between the ankle and knee movements during running. These results may help to explain why elderly individuals could be more susceptible to running-related injuries.
We have shown that stress fractures can be induced in the tibial diaphysis of an animal model by the repeated application of non-traumatic impulsive loads. The right hind limbs of 31 rabbits were loaded for three to nine weeks and changes in the bone were monitored by radiography and bone scintigraphy. The presence of stress fractures was confirmed histologically in some cases. Most animals sustained a stress fracture within six weeks and there was a positive correspondence between scintigraphic change and radiological evidence. Microscopic damage was evident at the sites of positive bone scans. The progression, location, and time of onset of stress fractures in this animal model were similar to those in clinical reports, making the model a useful one for the study of the aetiology of stress fractures.
Fifty-five male runners aged between 30 to 80 years were examined to determine the relative roles of various cardiovascular parameters which may account for the decrease in maximal oxygen uptake () with aging. All subjects had similar body fat composition and trained for a similar mileage each week. The parameters tested were, maximal heart rate (HR
max), cardiac output (Q), and arteriovenous difference in oxygen concentration (C
a —C
¯v) O2 during graded, maximal treadmill running. Average body fat and training mileage were roughly 12% and 50 km·week−1, respectively. The average 10-km runtime slowed significantly by 6.0%·decade−1 {[10-km run-time (min)=0.323 x age (years)+24.4] (n=49,r=0.692,p<0.001)}. A strong correlation was found between age and {[ (ml·kg−1·min−1)=- 0.439xage+76.5] (n=55,r=-0.768, p<0.001)}. Thus, decreased by 6.9%·decade−1 along with reductions ofHR
max (3.2%·decade−1, p<0.001) andQ (5.8%·decade−1, p<0.001), while no significant change with age was observed in estimated (C
a —C
¯v) O2. It was concluded that the decline of with aging in runners was mainly explained by the central factors (represented by the decline ofHR andQ in this study), rather than by the peripheral factor (represented by (C
a —C
¯v) O2).
Osteoporosis is a major public health problem that is characterized by low bone mass and increased susceptibility to fractures, primarily of the hip, spine, and wrist. It is estimated to cause 1.5 million fractures annually in the United States in people aged 50 yr and older. Physical activity, particularly weight-bearing exercise, is thought to provide the mechanical stimuli or "loading" important for the maintenance and improvement of bone health, whereas physical inactivity has been implicated in bone loss and its associated health costs. Both aerobic and resistance training exercise can provide weight-bearing stimulus to bone, yet research indicates that resistance training may have a more profound site specific effect than aerobic exercise. Over the past 10 years, nearly two dozen cross-sectional and longitudinal studies have shown a direct and positive relationship between the effects of resistance training and bone density. Conversely, a handful of other studies have reported little or no effect on bone density. However, these results may be partially attributable to the study design, intensity and duration of the exercise protocol, and the bone density measurement techniques used. High-intensity resistance training, in contrast to traditional pharmacological and nutritional approaches for improving bone health in older adults, has the added benefit of influencing multiple risk factors for osteoporosis including improved strength and balance and increased muscle mass.
Therapeutic stretching of the calf muscle-tendon unit is used to increase its length and to ameliorate decreased dorsiflexion range of motion (ROM), but the influence of age on the passive properties of the calf muscle-tendon unit has not been studied adequately The purpose of this study was to examine the influence of age on length and passive elastic stiffness (PES) characteristics of the calf muscle-tendon unit when stretched through the full, available dorsiflexion ROM.
Twenty-four younger women (aged 20-39 years), 24 middle-aged women (aged 40-59 years), and 33 older women (aged 60-84 years) participated.
An isokinetic dynamometer was used to passively stretch the right calf muscle-tendon unit from relaxed plantar flexion to the maximal angle of available dorsiflexion at 5(ús-1. The maximal passive resistive torque was measured, and passive angle-torque curves were constructed for a full ROM from an initial angle of passive resistive torque to the maximal dorsiflexion angle. The full ROM represented length extensibility. The average PES was calculated for this full stretch ROM and for the first half and the last half of this stretch ROM. The maximal passive dorsiflexion angle, maximal passive resistive torque, angular change for the full stretch ROM, and average PES for the full stretch ROM and the first half and the last half of the full stretch ROM were examined for group differences and their relationships with age.
The maximal passive dorsiflexion angle, maximal passive resistive torque, angular change for the full stretch ROM, and average PES within the last half of the full stretch ROM were less for the older women than for the younger women. Age was negatively associated with these variables.
Decreased maximal passive dorsiflexion ROM in older women was associated with decreased maximal passive resistive torque, decreased calf muscle-tendon unit length extensibility, and decreased average PES within the last half of their available passive dorsiflexion ROM.
The role of postactivation potentiation in enhancement of strength and speed performance requires further research
Postactivation potentiation (PAP), also known as activity-dependent potentiation, is an increase in muscle isometric twitch and low frequency tetanic force following a “conditioning” activity.1,2 Examples of conditioning activity are a series of evoked isometric twitches (staircase or treppe), an evoked isometric tetanic contraction (post-tetanic potentiation), a sustained isometric maximal voluntary contraction (MVC), and a series of dynamic contractions. In fact, any type of contractile activity is likely to activate the mechanism of PAP—that is, phosphorylation of myosin regulatory light chains, which increases Ca2+ sensitivity of the myofilaments.2 The result is an amplified level of myosin cross bridge activity in response to submaximal concentrations of myoplasmic Ca2+. A notable feature of PAP is that it has no effect on the force of high frequency tetanic isometric contractions, because in such contractions a “saturating” concentration of Ca2+ is attained, making any increase in Ca2+ sensitivity inconsequential. Although less studied, PAP also increases the force of shortening (concentric) contractions,3 and the highest frequency at which PAP is effective is greater for rapid shortening (concentric) contractions than for isometric contractions.4
On the basis of the foregoing, it would appear that PAP …
Tibial stress fractures (TSF) are among the most serious running injuries, typically requiring 6-8 wk for recovery. This cross-sectional study was conducted to determine whether differences in structure and running mechanics exist between trained distance runners with a history of prior TSF and those who have never sustained a fracture.
Female runners with a rearfoot strike pattern, aged between 18 and 45 yr and running at least 32 km.wk(-1), were recruited for this study. Participants in the study were 20 subjects with a history of TSF and 20 age- and mileage-matched control subjects with no previous lower extremity bony injuries. Kinematic and kinetic data were collected during overground running at 3.7 m.s(-1) using a six-camera motion capture system, force platform, and accelerometer. Variables of interest were vertical impact peak, instantaneous and average vertical loading rates, instantaneous and average loading rates during braking, knee flexion excursion, ankle and knee stiffness, and peak tibial shock. Tibial varum was measured in standing. Tibial area moment of inertia was calculated from tibial x-ray studies for a subset of runners.
The TSF group had significantly greater instantaneous and average vertical loading rates and tibial shock than the control group. The magnitude of tibial shock predicted group membership successfully in 70% of cases.
These data indicate that a history of TSF in runners is associated with increases in dynamic loading-related variables.
To investigate the stride pattern of different age groups of veteran runners in a marathon road race.
This kinematic study investigated the stride pattern (stride length, stride period, velocity, stance time, and non-stance time) for 151 runners (78 men aged up to 75-80, 73 women aged up to 60-64) at the 7 mile point.
Significant declines for men with aging were found for mean stride length (from 2.4 m at age 40-49 to 2.0 m at age 60+), velocity, and non-stance time (p<0.05), whereas stride period changed little. The findings indicate that the lower velocities of older runners are associated with shorter strides whereas cadence changes little. However, when a statistical adjustment was made for the variation in runners' velocity, it was found that older runners did not have a significantly shorter stride length at any given velocity.
Although a shorter stride is the mechanical route by which older runners lose velocity, the shorter stride may not be the fundamental cause of the velocity reduction with age. This has implications for researchers and coaches when investigating and training veteran distance runners.
The main function of bone is to provide the mechanical integrity for locomotion and protection; accordingly, bone mass and architecture are adjusted to control the strains produced by mechanical load and muscular activity. Age-related patterns involve peak bone mass during growth, a plateau in adulthood, and bone loss during aging. The decline in bone mass and structural integrity results in increased risk of fractures, particularly in post-menopausal women. Athletes competing in strength and power events, such as weight-lifting and jumping, have superior bone mass and structure compared with their untrained counterparts in all age groups. Exercise seems to be most effective during rapid growth, the average gain in bone mineral content (BMC) and density (BMD) in controlled trials being of the order of 2-5% per year. The net gain of BMD after exercise interventions among older people is modest, at a level of 1-3% per year, but it is not clear whether positive effects can be maintained over a longer time. Although aerobic exercise is important in maintaining overall health, the resistance type of muscle training may be more applicable to the basic rules of bone adaptation and site-specific effects of exercise, have more favorable effects in maintaining or improving bone mass and architecture, and be safe and feasible for older people. It has been suggested that there is an opportunity for resistance training, for improved effects on BMD in postmenopausal women in bones which have less daily loading. In addition to BMC and BMD, bone geometry and mass distribution may also change as a result of training and other treatment, such as hormonal replacement therapy, thereby further improving bone strength and reducing fracture risk. Appropriate training regimens may reduce the risk of falls and the severity of fall-related injuries, and also constitute potential therapy to improve functional ability and the quality of life in osteoporotic patients. However, further research is needed on dose-response relationships between exercise and bone strength, the feasibility of high-load, high-speed and impact-type of physical training, and the risks and benefits of intensive exercisein elderly individuals.
Tibial stress fractures are a serious overuse injury in runners. Greater vertical loading rates and tibial shock have been found in runners with previous tibial stress fracture compared to controls. The timing of these variables occurs very early in the stance phase and suggests that conditions shortly after footstrike may be important in determining injury risk. The purpose of this study was to further investigate lower extremity mechanics in early stance in runners with a history of tibial stress fracture. In addition, the relationships between these variables were explored.
Twenty-three runners with a history of tibial stress fracture were investigated. They were compared with 23 age and mileage matched control subjects with no previous lower extremity bony injuries. Data were collected as subjects ran at 3.7 m/s. All variables of interest were computed over the period from footstrike to the impact peak of the vertical ground reaction force. Independent t-tests and effect sizes were used to assess the differences between the groups. Pearson Product Moment correlations were used to determine whether initial stance variables were related to tibial shock in the two groups.
Sagittal plane knee stiffness was significantly greater in the tibial stress fracture group. Stiffness was also positively correlated with shock. Knee excursion, knee angle at footstrike and shank angle at footstrike were not different between groups.
These findings provide further support for the relationship between mechanics during initial loading and tibial stress fractures in runners. This relationship may be important in terms of retraining gait to reduce the risk of stress fracture in runners.