Hala Nassif - Academia.edu (original) (raw)

Papers by Hala Nassif

Science & Sports, 2012

Mesurer la reproductibilité et la pertinence des tests proposés par le protocole d'évaluation des... more Mesurer la reproductibilité et la pertinence des tests proposés par le protocole d'évaluation des capacités physiques Diagnoform Patients et résultats Cent quatre-vingt-trois sujets répartis par groupes d'âge et d'activité physique ont été évalués à deux reprises et les corrélations entre chaque test ont été calculées. La reproductibilité des tests est bonne à très bonne. Certains coefficients montrent une relation forte entre les tests mettant en jeu la puissance musculaire, suggérant une redondance dans l'évaluation de cette capacité. Conclusion La méthode Diagnoform est un outil efficace pour satisfaire aux objectifs d'évaluation de l'état de forme des populations.

Journal of Sports Science and Medicine, Jun 1, 2010

Sex is a major factor influencing best performances and world records. Here the evolution of the ... more Sex is a major factor influencing best performances and world records. Here the evolution of the difference between men and women's best performances is characterized through the analysis of 82 quantifiable events since the beginning of the Olympic era. For each event in swimming, athletics, track cycling, weightlifting and speed skating the gender gap is fitted to compare male and female records. It is also studied through the best performance of the top 10 performers in each gender for swimming and athletics. A stabilization of the gender gap in world records is observed after 1983, at a mean difference of 10.0% ± 2.94 between men and women for all events. The gender gap ranges from 5.5% (800-m freestyle, swimming) to 18.8% (long jump). The mean gap is 10.7% for running performances, 17.5% for jumps, 8.9% for swimming races, 7.0% for speed skating and 8.7% in cycling. The top ten performers' analysis reveals a similar gender gap trend with a stabilization in 1982 at 11.7%,...

ISEE Conference Abstracts

La prevalence de la sedentarite ne cesse d’augmenter et de progresser. L’inactivite physique est ... more La prevalence de la sedentarite ne cesse d’augmenter et de progresser. L’inactivite physique est la quatrieme cause de deces evitable: 1.9 millions de deces lui sont attribues dans le monde. Plusieurs etudes ont montre l’interet et le besoin de promouvoir l’activite physique dans differents milieux. Neanmoins, il reste un grand vide a combler entre la theorie, les politiques et le passage a l’acte. Cette these a pour but d’analyser et de developper des outils d’evaluations specifiques afin d’apporter la preuve de l’utilite des recommandations de promotion d’activite physique et de lutte contre la sedentarite. Notre premiere etude analyse les donnees d’un outil de mesure de condition physique en population generale sur un echantillon de 31 133 individus francais âges entre 8 et 60 ans. Nous avons evalue la fiabilite et la reproductibilite de l’outil. Par la suite, nous avons analyse le lien entre l’indice de masse corporelle, l’âge et les performances des differentes dimensions physi...

BMJ Open, 2012

Objective: To analyze the physical fitness level of 31 133 French citizens aged between 8 and 60 ... more Objective: To analyze the physical fitness level of 31 133 French citizens aged between 8 and 60 years old and represent the performances through a bi-exponential model. Methods: We collected data from 231 events that took place in French regions between 2006 and 2010 and analyzed participation and physical fitness using a simple series of tests. We assessed outcome measures in relation to age and BMI using Spearman Rho, a one way ANOVA and a bi-exponential model. Results: Our major results showed higher performances for men and for subjects with normal BMI at all age groups except for the flexibility test. Body mass index is strongly correlated across all ages with physical fitness p < 0.0001. Those results are in accordance with the literature. Furthermore, through a biexponential model, a mean peak performance was identified at 26.32 years old for men and 22.18 years old for women. Conclusion: Physical fitness assessment using simple tests is applicable on the general populati...

Actualité Dossier Santé …, 2009

développement de la communication, télévisuelle dans un premier temps, et informatique désormais,... more développement de la communication, télévisuelle dans un premier temps, et informatique désormais, n'est pas non plus sans conséquences sur ce ralentissement. Dans l'espèce humaine, le gradient de dépense énergétique va donc désormais de l'absence quasi ...

Journal of Sports …, 2010

©Journal of Sports Science and Medicine (2010) 9, 214-223 http://www.jssm.org ... Received: 07 De... more ©Journal of Sports Science and Medicine (2010) 9, 214-223 http://www.jssm.org ... Received: 07 December 2009 / Accepted: 02 March 2010 / Published (online): 01 June 2010 ... Women and men in sport performance: The gender gap has not evolved since 1983

No effect of weight cycling on the post-career BMI of weight class elite athletes

Environment International, 2011

Background: Substantial policy changes to control obesity, limit chronic disease, and reduce air ... more Background: Substantial policy changes to control obesity, limit chronic disease, and reduce air pollution emissions, including greenhouse gasses, have been recommended. Transportation and planning policies that promote active travel by walking and cycling can contribute to these goals, potentially yielding further cobenefits. Little is known, however, about the interconnections among effects of policies considered, including potential unintended consequences. Objectives and methods: We review available literature regarding health impacts from policies that encourage active travel in the context of developing health impact assessment (HIA) models to help decision-makers propose better solutions for healthy environments. We identify important components of HIA models of modal shifts in active travel in response to transport policies and interventions. Results and discussion: Policies that increase active travel are likely to generate large individual health benefits through increases in physical activity for active travelers. Smaller, but population-wide benefits could accrue through reductions in air and noise pollution. Depending on conditions of policy implementations, risk tradeoffs are possible for some individuals who shift to active travel and consequently increase inhalation of air pollutants and exposure to traffic injuries. Well-designed policies may enhance health benefits through indirect outcomes such as improved social capital and diet, but these synergies are not sufficiently well understood to allow quantification at this time. Conclusion: Evaluating impacts of active travel policies is highly complex; however, many associations can be quantified. Identifying health-maximizing policies and conditions requires integrated HIAs.

Journal of Sports Sciences, 2010

Road cycling ranks among the most intense endurance exercises. Previous studies and mathematical ... more Road cycling ranks among the most intense endurance exercises. Previous studies and mathematical models describing road cycling have not analysed performances per se. We describe the evolution of road cycling performance over the past 116 years. We studied the top ten cyclists&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; mean speeds in eight famous classic races and three European Grand Tours, using a previously published multi-exponential model that highlights the different progression periods of an event during the century. In addition, we measured an indicator of difficulty for the Tour de France by calculating the climbing index (i.e. the total altitude climbed over total distance). The eleven races&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; mean speed increased progressively from 23.13 km . h(-1) in 1892 to 41.19 +/- 2.03 km . h(-1) in 2008. Road cycling development, like other quantifiable disciplines, fits a piecewise progression pattern that follows three periods: before, between, and after the two World Wars. However, a fourth period begins after 1993, providing a speed progression of 6.38% from the third one. The Tour de France&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s climbing index also provided insight into a recent paradoxical relationship with speeds: when the climbing index increased, the winner&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s speed also increased. Our results show a major improvement (6.38%) in road cycling performance in the last 20 years and question the role of extra-physiological parameters in this recent progression.

Materials Today, 2010

The science of engineering materials and the development of materials science during human histor... more The science of engineering materials and the development of materials science during human history have strongly evolved over the past two centuries 1,2 . Other new technological fields such as particle physics, computer science, nanoscience also flourished 3 , all leading to innovations that impacted sport. Polymers and metal alloys such as carbon fibres are exemplars of materials now widely used in various disciplines 4 . In 2008, polyurethane made its first appearance in swimming with the use of a new swimsuit generation. The result was a sudden improvement of performances, allowing athletes to go beyond physiological limits that have been nearly reached 5,6 . This study aimed to quantify the gain provided by the three generations of swimsuits introduced in 1999, 2008, 2009 and to estimate the upcoming performance drop in 2010. Using a recently published methodology 7 , we analyzed the single best result each year for the world's top ten swimmers from 1990 to 2009 in order to assess the sudden progression trends and quantify the total performance gain.

The victory percentages for tennis players who entered the top 10 women and men rankings show var... more The victory percentages for tennis players who entered the top 10 women and men rankings show various evolutions related to age and time since 1968. The study analyzed the careers of all top 10 players: 97 women (50,933 matches) and 144 men (92,450 matches). For each player, we describe a biphasic performance course. Two generations were compared: the first one (G1), including players who started their professional career before 1985, and the second one (G2), with players starting after 1985. The average career length is 16.1 ± 3.8 yr for the top 10 men and 15.8 ± 4.4 yr for women. Compared with G1 players, G2 players begin earlier (women = 1.3 yr, men = 0.8 yr), but career length remains the same. An exponential model describes the time course of the victory percentage with a great similarity for both genders. Using this equation, the peak victory rate reaches 82.5% at 21.5 yr for number 1 (no. 1) women and 78.5% at 23.7 yr for no. 1 men, showing a greater precocity and earlier decline in women. Finally, the area under the curve shows a potential that is 22.8% (men) to 56.8% (women) larger for the no. 1 players as compared with all other numbers 2-10. Tennis players in the top 10 show a biphasic career. Women reach their highest level earlier than men, consistent with their more precocious biological development. For the current generation, the peak performance tends toward a younger age than the first generation. We show how to precisely quantify and compare tennis performances using indicators that follow the trends of development and aging and demonstrate that precocity does not provide a larger victory potential.

Objective: To analyse the physical fitness of a large sample of the French population across diff... more Objective: To analyse the physical fitness of a large sample of the French population across different ages. Design: Observational cross-sectional study. Setting: Data were collected from the Athletic Track and Field Federation, which organised events dedicated to measuring physical fitness. The events took place in 22 regions between 2006 and 2010.

BMC Public Health, 2013

Background: Repetitions of pre-competition weight-loss diets done by athletes participating in we... more Background: Repetitions of pre-competition weight-loss diets done by athletes participating in weight class sports can be regarded as periods of weight cycling. The aim of the present study is to identify the long term post-career (22 years) evolutionary profile of athletes' BMI after such weight cycling. Methods: One hundred and thirty-six retired French athletes who participated in major international competitions in weight class sports (rowers, wrestlers, boxers, and judokas) were included. Former and current body mass, height, dietary characteristics during the career (annual frequency, amount of weight lost), current physical activity, and answers on the eating-attitude test were collected by phone interview (consistency was tested by comparison with measured weight). We performed ANOVA tests for comparison between groups (sport, dieting), post-hoc tests (Bonferroni test) to identify differences within groups. BMI's changes were treated using a mixed model. Results: The recorded weight changes did not depend upon time since retirement. Between 18 y and 50 y, athletes' BMI increased by 3.2 kg/m 2 compared to the 4.2 kg/m 2 increase in the general population. This increase was independent of the number of diets during the career. Retired athletes declared a mean weekly physical activity of 4.8 h ± 4.3. The eating-attitude test showed low scores for all sports without any correlation to diet characteristics.

Archives of Physical Medicine and Rehabilitation, 2011

PLoS ONE, 2009

A previous analysis of World Records (WR) has revealed the potential limits of human physiology t... more A previous analysis of World Records (WR) has revealed the potential limits of human physiology through athletes' personal commitment. The impact of political factors on sports has only been studied through Olympic medals and results. Here we studied 2876 WR from 63 nations in four summer disciplines. We propose three new indicators and show the impact of historical, geographical and economical factors on the regional WR evolution. The south-eastward path of weighted annual barycenter (i.e. the average of country coordinates weighting by the WR number) shows the emergence of East Africa and China in WR archives. Home WR ratio decreased from 79.9% before the second World War to 23.3% in 2008, underlining sports globalization. Annual Cumulative Proportions (ACP, i.e. the cumulative sum of the WR annual rate) highlight the regional rates of progression. For all regions, the mean slope of ACP during the Olympic era is 0.0101, with a maximum between 1950 and 1989 (0.0156). For European countries, this indicator reflects major historical events (slowdown for western countries after 1945, slowdown for eastern countries after 1990). Mean North-American ACP slope is 0.0029 over the century with an acceleration between 1950 and 1989 at 0.0046. Russia takes off in 1935 and slows down in 1988 (0.0038). For Eastern Europe, maximal progression is seen between 1970 and 1989 (0.0045). China starts in 1979 with a maximum between 1990 and 2008 (0.0021), while other regions have largely declined (mean ACP slope for all other countries = 0.0011). A similar trend is observed for the evolution of the 10 best performers. The national analysis of WR reveals a precise and quantifiable link between the sport performances of a country, its historical or geopolitical context, and its steps of development.

Journal of Criminal Justice - J CRIM JUSTICE, 2011

L’augmentation de la sédentarité des français et la diminution de la pratique des activités physi... more L’augmentation de la sédentarité des français et la diminution de la pratique des activités physiques ou sportives (APS) favorables à la santé suscitent de nombreuses tentatives publiques et campagnes de promotion visant à favoriser la dépense énergétique. Mais si la conscience de ce déséquilibre apparaît de plus en plus clairement dans la population, le passage à l’acte est encore loin d’être réussi. C’est pourquoi se mettent en place de nombreux groupes de travail et de réflexion cherchant à élargir les champs d’action mais surtout à tirer parti de tous les environnements favorables à cette remise en forme. L’école, l’entreprise, les collectivités territoriales ou les acteurs du sport (clubs, ligues, associations) sont de plus en plus impliqués dans la participation à ce grand mouvement, qui verra, par le biais du PNNS 2011–2015, croître l’investissement dans un domaine un peu négligé jusque là : celui de l’équilibre énergétique.The increase of sedentary lifestyle in the French population and the decrease in the time daily devoted to physical activity has raised public concerns. Promotional campaigns to raise energy expenditure and health awareness have recently increased. Nevertheless, although the recognition of such an imbalance is becoming more evident in the population, a real beneficial modification is still far from a full success. Numerous working groups are seeking to broaden the scope of action and take advantage of environments that facilitate the application of strategies. Local settings such as schools, businesses, urban authorities and sports representatives (clubs, leagues and associations) progressively increase their engagement. Through large collective participations gathered in the PNNS initiative (Plan National Nutrition Santé 2011–2015), we may witness a growing investment in the energy balance, an area that has been neglected so far.

The growth law for the development of top athletes performances remains unknown in quantifiable s... more The growth law for the development of top athletes performances remains unknown in quantifiable sport events. Here we present a growth model for 41351 best performers from 70 track and field (T&F) and swimming events and detail their characteristics over the modern Olympic era. We show that 64% of T&F events no longer improved since 1993, while 47% of swimming events stagnated after 1990, prior to a second progression step starting in 2000. Since then, 100% of swimming events continued to progress. We also provide a measurement of the atypicity for the 3919 best performances (BP) of each year in every event. The secular evolution of this parameter for T&F reveals four peaks; the most recent (1988) followed by a major stagnation. This last peak may correspond to the most recent successful attempt to push forward human physiological limits. No atypicity trend is detected in swimming. The upcoming rarefaction of new records in sport may be delayed by technological innovations, themselves depending upon economical constraints.

PloS one, 2011

Objectives: Few epidemiological studies have focused on the psychological health of high level at... more Objectives: Few epidemiological studies have focused on the psychological health of high level athletes. This study aimed to identify the principal psychological problems encountered within French high level athletes, and the variations in their prevalence based on sex and the sport practiced.