In this editorial, we focus on recent problematic developments in sport science, and more specifically, problems related to periodization research. Primary areas discussed are (1) appreciation of history, (2) considerations for training studies, (3) the development of concepts, and (4) programming-driven training models.

Ideally an athlete would continue to improve performance indefinitely over time, however improvement slows as the athlete approaches their genetic limits. Measuring performance is complex—performance may be temporarily depressed following aggressive training for multiple reasons, physiological and psychosocial. This reality may be vexing to the strength and conditioning coach, who, as a service provider, must answer to sport coaches about an athlete’s progress. Re-cently an evaluation mechanism for strength and conditioning coaches was proposed, in part to help coaches establish their effectiveness within the organization. Without formal guidance and realistic expectations, if an athlete is not bigger, leaner, stronger, etc. as a result of training within a specified timeframe, blame is often placed upon the strength and conditioning coach. The purpose of this article is to explore possible causes of what may be perceived as athlete non-responses to training and to provide guidance for the coach on how to handle those issues within their domain. A process of investigation is recommended, along with resources to assist coaches as they consider a broad range of issues, including enhancing existing testing methods, improving athlete behaviors, and adjusting processes designed to bring about performance improvement.

Aim: The purpose of this study was: 1) to investigate the alterations and relationships among training variables, performance variables, and physiological variables and 2) investigate the effects of strength training on potentiation complexes. Methods: The study enrolled nine D-1 collegiate throwers and four control subjects. The throwers participated in an 11-week resistance training and throws program. Resistance training volume load and throwing volume were recorded for 11 weeks. Measurements of maximal strength (isometric mid-thigh pulls) and dynamic mid-thigh pulls (DMTP) across a spectrum of loads: Males-60kg, 140kg, 180kg, 220kg, 140kg, 30% isometric peak force (IPF), Females - 60kg, 80kg, 100kg, 120kg, 80kg, 30% IPF), were measured at weeks 1, 7, and 11. The control group was tested for isometric maximum strength at T1 (week 1) and T3 (week 11) Results: The throwers increased at each time point in isometric peak force (IPF), allometrically scaled IPF (IPFa), and isometric impulse. The throwers strength (IPF and IPFa) was significantly greater than the controls and the throwers experienced statistically significant changes in maximum strength from T1 to T3 when compared to the controls. The throwers demonstrated statistically significant changes in total load variables (variable for load 1+ load 2 + load 3 etc.) for DMTPs. Conclusion. As a whole these data suggest a potential for increased performance capabilities specific to throwing. Some data trends indicate that potentiation can occur as a result of performing a heavy pull before a lighter one. However, increasing maximum strength as a result of focusing on strength training did not enhance this potentiation effect.

Aim. The purpose of this study was to evaluate the relationship between weightlifting performance (snatch, clean and jerk, and total) and variables obtained from the isometric mid-thigh pull (IMTP). Methods. Twelve weightlifters, ranging from novice to advanced, performed the IMTP 10 days after a competition. Correlations were used to evaluate relationships between variables of the IMTP and absolute and scaled competition results. Results. Unsealed competition results correlated strongly with IRFD (0-200ms: r=0.567-0.645, 0-250ms: r=0.722-0.781) while results correlated weakly with Peak IRFD (5ms window, r=0.360-0.426). Absolute peak force values correlated very strongly with absolute values for the competition performance (r=0.830-0.838). Force at 100ms, 150ms, 200ms and 250ms also correlated strongly with competition results (r=0.643-0.647, r=0.605-0.636, r=0.714-0.732, r=0.801-0.804). Similar findings were noted for allometrically scaled values. Conclusion. Measures of average IRFD probably represent a more relevant variable to dynamic performance than does Peak IRFD (5ms). Maximum isometric strength also is likely to have a strong role in weightlifting performance.

Aim: The purpose of this study was: 1) to investigate the alterations and relationships among training variables, performance variables, and physiological variables and 2) investigate the effects of strength training on potentiation complexes. Methods: The study enrolled nine D-1 collegiate throwers and four control subjects. The throwers participated in an 11-week resistance training and throws program. Resistance training volume load and throwing volume were recorded for 11 weeks. Measurements of maximal strength (isometric mid-thigh pulls) and dynamic mid-thigh pulls (DMTP) across a spectrum of loads: Males-60kg, 140kg, 180kg, 220kg, 140kg, 30% isometric peak force (IPF), Females - 60kg, 80kg, 100kg, 120kg, 80kg, 30% IPF), were measured at weeks 1, 7, and 11. The control group was tested for isometric maximum strength at T1 (week 1) and T3 (week 11) Results: The throwers increased at each time point in isometric peak force (IPF), allometrically scaled IPF (IPFa), and isometric impulse. The throwers strength (IPF and IPFa) was significantly greater than the controls and the throwers experienced statistically significant changes in maximum strength from T1 to T3 when compared to the controls. The throwers demonstrated statistically significant changes in total load variables (variable for load 1+ load 2 + load 3 etc.) for DMTPs. Conclusion. As a whole these data suggest a potential for increased performance capabilities specific to throwing. Some data trends indicate that potentiation can occur as a result of performing a heavy pull before a lighter one. However, increasing maximum strength as a result of focusing on strength training did not enhance this potentiation effect.

Aim. The purpose of this study was to evaluate the relationship between weightlifting performance (snatch, clean and jerk, and total) and variables obtained from the isometric mid-thigh pull (IMTP). Methods. Twelve weightlifters, ranging from novice to advanced, performed the IMTP 10 days after a competition. Correlations were used to evaluate relationships between variables of the IMTP and absolute and scaled competition results. Results. Unsealed competition results correlated strongly with IRFD (0-200ms: r=0.567-0.645, 0-250ms: r=0.722-0.781) while results correlated weakly with Peak IRFD (5ms window, r=0.360-0.426). Absolute peak force values correlated very strongly with absolute values for the competition performance (r=0.830-0.838). Force at 100ms, 150ms, 200ms and 250ms also correlated strongly with competition results (r=0.643-0.647, r=0.605-0.636, r=0.714-0.732, r=0.801-0.804). Similar findings were noted for allometrically scaled values. Conclusion. Measures of average IRFD probably represent a more relevant variable to dynamic performance than does Peak IRFD (5ms). Maximum isometric strength also is likely to have a strong role in weightlifting performance.

Gymnastics tumbling has occurred on large spring floor apparatuses for several decades. The spring floors have used a variety of elastic materials and designs to provide an increased take-off velocity and a forgiving landing surface. The purpose of this study was to assess the efficacy of a standard cylindrical spring (10.7 cm x 5 cm diameter, 9 coils) and a modified spring (10.7 cm, 5 cm widening to 6.7 cm diameter, 9 coils) in tumbling take-offs. Specifically, take-off foot contact durations and center of mass (COM) velocities from female gymnasts (14.8±2.8 y, 159.0±7.2 cm, 49.3±7.1 kg) were measured. Gymnasts performed two trials each of a round off, flic flac, to a layout rearward somersault on each spring-type attached to a tumbling strip (12.19m x 2.41m). Data were acquired via a ViconTM kinematic system using 43 markers and 10 cameras at 200 Hz. Data were found to be reliable across trials. Analysis consisted of two, 2x3 repeated measures ANOVAs. The results showed no statistical differences between spring-types in terms of contact durations or COM component velocities. Spring-type design differences may lead to disparate spring constant and frequency effects, however, these effects of may be overwhelmed by the influences of gymnast skill, matting, carpet, and the wood and fiberglass laminate panels.

Aim. The aim of the study was to investigate the applicability of a repeated change-of-direction (RCoD) test for NCAA Division-I male soccer players. Methods. The RCoD test consisted of 5 diagonal direction changes per repetition with a soccer ball to be struck at the end. Each player performed 15 repetitions with approximately 10 seconds to jog back between repetitions. Data were collected in two sessions. In the first session, 13 players were examined for heart rate responses and blood lactate concentrations. In the second session, 22 players were examined for the test's ability to discriminate the primary from secondary players (78.0±16.1 and 10.4±13.3 minutes per match, respectively). Results. Heart rate data were available only from 9 players due to artifacts. The peak heart rate (200.2±6.6 beats·min-1: 99.9±3.0% maximum) and blood lactate concentration (14.8±2.4 mmol·L-1 immediately after) resulted in approximately 3.5 and 6.4-fold increases from the resting values, respectively. These values appear comparable to those during intense periods of soccer matches. In addition, the average repetition time of the test was found to discriminate the primary (4.85±0.23 s) from the secondary players (5.10±0.24 s) (P=0.02). Conclusion. The RCoD test appears to induce physiological responses similar to intense periods of soccer matches with respect to heart rate and blood lactate concentration. Players with better average repetition times tend to be those who play major minutes.

The current manuscript is a translation of the Position statement on youth resistance training: the 2014 International Consensus. The original manuscript was adapted from the oficial position statement of the UK Strength and Conditioning Association on youth resistance training. It was subsequently reviewed and endorsed by leading professional organisations within the fields of sports medicine, exercise science and paediatrics. The authorship team for this article was selected from the fields of paediatric exercise science, paediatric medicine, physical education, strength and conditioning and sports medicine.

Trends in pairs figure skating have shown that increasingly difficult jumps have become an essential aspect of high-level performance, especially in the latter part of a competitive program. We compared a repeated jump power index in a 60 s repeated jump test to determine the relationship of repeated jump test to competitive rank and to measure 2D hip, knee, and ankle angles and angular velocities at 0, 20, 40, and 60 s. Eighteen National Team Pairs Figure Skaters performed a 60 s repeated jump test on a large switch-mat with timing of flight and ground durations and digital video recording. Each 60-s period was divided into 6, 10-s intervals, with power indexes (W/kg) calculated for each 10-s interval. Power index by 10-s interval repeated measures ANOVAs (RMANOVA) showed that males exceeded females at all intervals, and the highest power index interval was during 10 to 20 s for both sexes. RMANOVAs of angles and angular velocities showed main effects for time only. Power index and jumping techniques among figure skaters showed rapid and steady declines over the test duration. Power index can predict approximately 50% of competitive rank variance, and sex differences in jumping technique were rare.