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Maria Francesca Piacentini and Romain Meeusen

Purpose:

This longitudinal case study evaluated the effectiveness of an online training-monitoring system to prevent nonfunctional overreaching (NFOR).

Methods:

A female master track and field athlete was followed by means of a daily online training diary (www.spartanova.com) and a weekly profile of mood state (POMS). The online diary consists of objective training data and subjective feelings reported on a 10-cm visual analog scale. Furthermore, parameters that quantify and summarize training and adaptation to training were calculated. The novelty consists in the inclusion of a specific measuring parameter tested to detect NFOR (OR score).

Results:

During track-season preparation, the athlete was facing some major personal changes, and extratraining stress factors increased. Despite the fact that training load (TL) did not increase, the or score showed a 222% and then a 997% increase compared with baseline. POMS showed a 167% increase in fatigue, a 38% decrease in vigor, a 32% increase in depression scores, and a total mood increase of 22%, with a 1-wk shift compared with the OR score. A 41% decrease in TL restored the OR score and POMS to baseline values within 10 d.

Conclusion:

The results demonstrate that immediate feedback obtained by “warning signals” to both athletes and coaches, based on individual baseline data, seems an optimal predictor of FOR/NFOR.

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Simon Wang and Stuart M. McGill

Spine stability is ensured through isometric coactivation of the torso muscles; however, these same muscles are used cyclically to assist ventilation. Our objective was to investigate this apparent paradoxical role (isometric contraction for stability or rhythmic contraction for ventilation) of some selected torso muscles that are involved in both ventilation and support of the spine. Eight, asymptomatic, male subjects provided data on low back moments, motion, muscle activation, and hand force. These data were input to an anatomically detailed, biologically driven model from which spine load and a lumbar spine stability index was obtained. Results revealed that subjects entrained their torso stabilization muscles to breathe during demanding ventilation tasks. Increases in lung volume and back extensor muscle activation coincided with increases in spine stability, whereas declines in spine stability were observed during periods of low lung inflation volume and simultaneously low levels of torso muscle activation. As a case study, aberrant ventilation motor patterns (poor muscle entrainment), seen in one subject, compromised spine stability. Those interested in rehabilitation of patients with lung compromise and concomitant back troubles would be assisted with knowledge of the mechanical links between ventilation during tasks that impose spine loading.

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Afroditi Stathi and Simon J. Sebire

Background:

Inner-city schools experience substantial difficulties in providing sufficient physical activity opportunities for their pupils. This study evaluated the Y-Active, an outreach physical activity and well-being program delivered in an inner-city primary school in London, UK by a third-sector partner.

Methods:

A process evaluation focusing on perceived effectiveness and implementation issues was conducted using qualitative case-study methodology. Semistructured interviews and focus groups were conducted with Year 5 and Year 6 pupils (N = 17, age range = 9 to 11 years), Y-Active sports leaders (N = 4), the school head teacher, class teachers (N = 2), and the Y-Active administrator. Transcripts were thematically analyzed and multiple informant and analyst triangulation performed.

Results:

The Y-Active leaders created a positive learning environment supporting autonomy, balancing discipline and structure and providing self-referenced feedback, excellence in tuition and a strong focus on fun and praise. Pupils reported improvements in self-confidence and competence, self-discipline and interpersonal relationships. School staff and Y-Active leaders highlighted that their partnership was built on trust, top-down leadership support and open lines of communication between the provider and the school.

Conclusions:

Collaboration between third sector service providers and inner-city schools represents a promising means of increasing children’s physical activity and well-being.

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Gerasimos Terzis, Thomas Kyriazis, Giorgos Karampatsos and Giorgos Georgiadis

Purpose:

Although muscle mass and strength are thought to be closely related to throwing performance, there are few scientific data about these parameters in elite shot-putters. The purpose of this case report was to present longitudinal data for muscle strength and body composition in relation to performance of an elite male shot-putter.

Methods:

A male national champion with the best rotational shot-put performance of 20.36 m (in 2010) was followed from 2003 to 2011 (current age: 29 y). Data regarding body composition (dual X-ray absorptiometry), as well as 1-repetition-maximum muscle strength (bench press, squat, snatch) and rotational shot-put performance, were collected every February for the last 9 y, 4 wk before the national indoor championship event.

Results:

The athlete’s personal-best performances in squat, bench press, and snatch were 175 kg, 210 kg, and 112.5 kg, respectively. His peak total lean body mass was 92.4 kg, bone mineral density 1.55 g/cm2, and lowest body fat 12.9%. His shot-put performance over these 9 years was significantly correlated with 1-repetition-maximum squat strength (r = .93, P < .01), bench press (r = .87, P < .01), and snatch (r = .92, P < .01). In contrast, shot-put performance was not significantly correlated with any of the body-composition parameters.

Conclusions:

The results of this case study suggest that elite rotational shot-put performance may not be directly correlated with lean body mass. Instead, it seems that it is closely related with measures of muscle strength.

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Ana Anton-Solanas, Barry V. O’Neill, Tessa E. Morris and Joe Dunbar

Purpose:

To assess changes in body composition and monitor cognitive function, subjective well-being, and physiological stress, as measured by salivary hormones and markers of mucosal immunity, during an Antarctic expedition.

Methods:

A 36-y-old man (188.2 cm height, 94.5 kg body mass) took part in a world-record attempt. A total-body dual-energy X-ray absorptiometry scan and measurement of 8 skinfolds and 5 girths were performed before and after the expedition. In addition, daily subjective data were recorded (sleep quality, total hours of sleep, energy levels, perceived exertion, mood, muscle soreness, and muscle/joint pain) along with distance covered and hours of physical activity per day. As a measure of cognitive function, the athlete completed a computerized battery of tasks (Axon Sports Cognitive Priming Application) every third morning. Saliva samples were collected before, during, and after the expedition to determine salivary cortisol (sCort), testosterone (sT), alpha amylase (sAA), and secretory immunoglobulin A (sIgA).

Results:

The athlete lost 5.3 kg body mass and sum of 8 skinfolds decreased from 73 mm to 59 mm from preexpedition to postexpedition. Psychomotor speed declined over the course of the expedition. sT increased and sCort decreased throughout, and sAA and sIgA peaked toward the end of the expedition.

Conclusions:

This case study provides novel data about the physiological and cognitive impact of an Antarctic expedition. The findings may inform strategies for future expeditions, allowing individuals undertaking expeditions of this nature to better prepare for success.

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Torben Pottgiesser, Laura A. Garvican, David T. Martin, Jesse M. Featonby, Christopher J. Gore and Yorck O. Schumacher

Hemoglobin mass (tHb) is considered to be a main factor for sea-level performance after “live high–train low” (LHTL) altitude training, but little research has focused on the persistence of tHb following cessation of altitude exposure. The aim of the case study was to investigate short-term effects of various hematological measures including tHb upon completion of a simulated altitude camp. Five female cyclists spent 26 nights at simulated altitude (LHTL, 16.6 ± 0.4 h/d, 3000 m in an altitude house) where tHb was measured at baseline, at cessation of the camp, and 9 d thereafter. Venous blood measures (hemoglobin concentration, hematocrit, %reticulocytes, serum erythropoietin, ferritin, lactate dehydrogenase, and haptoglobin) were determined at baseline; on day 21 during LHTL; and at days 2, 5, and 9 after LHTL. Hemoglobin mass increased by 5.5% (90% confidence limits [CL] 2.5 to 8.5%, very likely) after the LHTL training camp. At day 9 after simulated LHTL, tHb decreased by 3.0% (90%CL −5.1 to −1.0%, likely). There was a substantial decrease in serum EPO (−34%, 90%CL −50 to −12%) at 2 d after return to sea level and a rise in ferritin (23%, 90%CL 3 to 46%) coupled with a decrease in %reticulocytes (−23%, 90%CL −34 to −9%) between day 5 and 9 after LHTL. Our findings show that following a hypoxic intervention with a beneficial tHb outcome, there may be a high probability of a rapid tHb decrease upon return to normoxic conditions. This highlights a rapid component in red-cell control and may have implications for the appropriate timing of altitude training in relation to competition.

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Dajo Sanders, Mathieu Heijboer, Ibrahim Akubat, Kenneth Meijer and Matthijs K. Hesselink

Purpose:

To assess if short-duration (5 to ~300 s) high-power performance can accurately be predicted using the anaerobic power reserve (APR) model in professional cyclists.

Methods:

Data from 4 professional cyclists from a World Tour cycling team were used. Using the maximal aerobic power, sprint peak power output, and an exponential constant describing the decrement in power over time, a power-duration relationship was established for each participant. To test the predictive accuracy of the model, several all-out field trials of different durations were performed by each cyclist. The power output achieved during the all-out trials was compared with the predicted power output by the APR model.

Results:

The power output predicted by the model showed very large to nearly perfect correlations to the actual power output obtained during the all-out trials for each cyclist (r = .88 ± .21, .92 ± .17, .95 ± .13, and .97 ± .09). Power output during the all-out trials remained within an average of 6.6% (53 W) of the predicted power output by the model.

Conclusions:

This preliminary pilot study presents 4 case studies on the applicability of the APR model in professional cyclists using a field-based approach. The decrement in all-out performance during high-intensity exercise seems to conform to a general relationship with a single exponential-decay model describing the decrement in power vs increasing duration. These results are in line with previous studies using the APR model to predict performance during brief all-out trials. Future research should evaluate the APR model with a larger sample size of elite cyclists.

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Laura Capranica and Mindy L. Millard-Stafford

A prevailing theory (and practical application) is that elite performance requires early childhood skill development and training across various domains, including sport. Debate continues whether children specializing early (ie, training/competition in a single sport) have true advantage compared with those who sample various sports early and specialize in a single sport later (adolescence). Retrospective data and case studies suggest either model yields elite status depending upon the sport category (ie, situational: ball games, martial arts, fencing; quantitative: track and feld, swimming, skiing; or qualitative: gymnastics, diving, figure skating). However, potential risks of early specialization include greater attrition and adverse physical/emotional health outcomes. With the advent of the IOC Youth Olympic Games, increased emphasis on global youth competition has unknown implications but also represents a potential platform for investigation. Modification of youth competition formats should be based upon multidisciplinary research on psycho-physiological responses, and technical-tactical behaviors during competition. The assumption that a simple scaled-down approach of adult competitions facilitates the development of technical/tactical skills of youth athletes is not necessarily substantiated with field-based research. Relatively little evidence exists regarding the long-term effects of rigorous training and competitive schedules on children in specific sports. It is clear that more prospective studies are needed to understand the training dose that optimally develops adaptations in youth without inducing dropout, overtraining syndrome, and/or injury. Such an approach should be sport specific as well as gender based. Until such evidence exists, coaches and sport administrators will continue to rely upon their sport-specific dogma to influence programmatic development of our most vulnerable population.

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Stephen A. Ingham, Barry W. Fudge and Jamie S. Pringle

This case study observed the training delivered by a 1500-m runner and the physiological and performance change during a 2-y period. A male international 1500-m runner (personal best 3:38.9 min:s, age 26 y, height 1.86 m, body mass 76 kg) completed 6 laboratory tests and 14 monitored training sessions, during 2 training years. Training distribution and volume was ascertained from training diary and spot-check monitoring of heart rate and accelerometry measurements. Testing and training information were discussed with coach and athlete from which training changes were made. In the first training year, low-intensity training was found to be performed above the prescribed level, which was adjusted with training and coach support in y 2 (training zone < 80% of vVO2max, y 1 = 20%; y 2 = 55%). “Tempo” training was also performed at an excessively high intensity (Δ [blood lactate] 5–25 min of tempo run, y 1 = Δ6.7 mM, y 2 = Δ2.5 mM). From y 1 to 2, there was a concomitant increase in the proportion of training in the high-intensity zone of 100 to 130% vVO2max from 7 to 10%. Values for VO2max increased from 72 to 79 mL · kg−1 · min, economy improved from 210 to 206 mL · kg−1 · min, and 1500-m performance time improved from 3:38.9 to 3:32.4 min:s from the beginning of y 1 to the end of y 2. This case shows a modification in training methodology that was coincident with a greater improvement in physiological capability and furtherance in performance improvement.

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H. Jan Dordel

Individuals with severe physical and psychomotor modifications after a brain injury need measures of motor training beyond the usual physiotherapy. The effects of an intensive mobility training in the phase of late rehabilitation are reported in two case studies. The coordinative and conditional progresses were controlled by the methods of photographic anthropometry, light-track registration, and bicycle ergometry. Improvements were found in posture and dynamic endurance in correlation with the generally improving motor control. Tests of everyday relevant movements revealed qualitative progresses in the sense of increased motor precision and economy.