Specific relationships between physical activity & mental health: the importance of considering gender & refining recommendations

Although there is good reason for promoting physical activity in the general public, both as preventive measure and as means of improving mental and social well-being1, physical activity promotion meant for the promotion of mental health is a rarity. Not even a simple message for the amount and type of physical activity for optimal mental health exists, and physical activity recommendations only tangentially deal with the potential of physical activity for mental health benefits. The current state of matters regarding the physical activity – mental health relationship is that the question of whether physical activity results in mental health benefits, or better mental health increases the likeliness of participation in physical activity, which in turn accounts for the research findings confirming a positive relationship between physical activity and mental health, seems impossible to answer. The direction of causality in this relationship remains undetermined, mainly because a substantial number of variables align and change in the physical activity – mental health relationship, making it much more complex than the relationship between physical activity and physical health. The aim of the present thesis was to create a more differentiated picture about the relationship between physical activity and mental health, in order to disentangle some of its great complexity, and perhaps help strengthening statements about it. The potential of physical activity to improve psychological functioning was comprehensively considered, from protecting against mental health problems to promoting self-awareness and personal growth. The thesis includes an in-depth review of the historical and current knowledge on the topics under scrutiny, and it focuses on three main coordinates on which the complexity of the physical activity – mental health relationship appears to manifest: activity domains (i.e., different types and intensities of physical activity), domains of mental health (e.g., emotional well-being, depression, anxiety, perceived stress, psychological distress, stress appraisal), and individual differences (gender differences in particular). Variations within and between these coordinates were analyzed with an epidemiological approach. Empirical hypotheses were developed based on the information derived from the extensive literature review. The thesis includes four original research articles, which are based on data from two large and representative cohorts in Belgium; one from the Belgian Health Interview Survey (B-HIS), including a total of 12,111 participants; 6,190 women (51.1%) and 5,921 men (48.9%), aged 0-99 years, representing the entire Belgian population, and another from the Flemish Policy Research Centre Sport, Physical Activity, and Health (SPAH), including 5,170 individuals; 2,746 men (53.1%) and 2,420 women (46.9%), aged 18-75 years, from 46 Flemish municipalities, representing the whole Flanders (the Northern part of Belgium). The first study differentiated between recreational and utilitarian forms of physical activity in their relation with levels of self-reported stress and distress in 1,919 adults aged 20-65 years, from the SPAH epidemiological data. Multiple Logistic Regression analyses were conducted, stratified by gender, age, and occupational category. Results were integrated in an adequate theoretical frame, resulting the proposition that although physical activities of any content may be beneficial for physical health, when targeting psychological benefits, it may perhaps be insufficient to just climb the stairs instead of taking the elevator, or to engage in housework or gardening. The discussion on the findings revealed the question of whether the importance of motivation and enjoyment of physical activity is greater regarding mental health benefits than concerning physical health benefits. The second study differentiated between physical activities of three different intensities and five components of mental health, including general (i.e., emotional well-being) and specific (i.e., depression, anxiety, somatization, and sleeping problems) components of mental health. Gender specific multiple Logistic Regression analyses were conducted in 3,435 women and in 3,368 men aged 25-64 years from the B-HIS data. Findings suggested clear gender differences in the optimal intensity levels of the physical activity that associates with better mental health. Positive associations between physical activity and mental health in men included vigorous-intensity physical activity and specific components of mental health, whereas among women, it involved moderate-intensity physical activity and walking with both general and specific components of mental health. The third study relied on previous findings suggesting that sports participation might associate stronger with mental health than other types of physical activity (e.g., Hamer et al., 2008) and on Salmon’s (2001) unifying theory on how the role of physical activity in stress management might explain the physical activity – mental health relationship. Associations between participation in personally favored types of sports and stress appraisal and emotional distress were examined separately in 783 sport participator men and in 644 sport participator women, aged 20-65 years, from the SPAH epidemiologic data. Multiple MANOVAs were conducted to analyze sport-type related variations (including 15 different types of sports) in the physical activity – mental health relationship. The findings were used in theoretical reasoning about the possible meanings that women and men might attach to their sports participation, which resulted in the presupposition that men might attach a meaning of distancing or escapism, while women might attach a meaning of developing self-awareness to participation in sports. The fourth study aimed to gather insight about the relationship between sedentary behavior and mental health, based on the physical activity – sedentary behavior, and the physical activity – mental health relationships. Variations across gender, age, socio-economic status, and participation in recommended amounts of vigorous- and moderate-intensity physical activity were analyzed in the associations between sedentary time and five components of mental health, in 6,720 adults aged 24-65years, from the BHIS data. Sedentary time and physical activity were separately measured, and examined via multiple Logistic Regression analyses; hence, the findings conveyed understanding of the potential independent mental health outcomes of sedentary behavior. The present thesis does not provide proof of the positive effects of physical activity on mental health because the cross-sectional studies could not affirm that physical activity causes improvements in mental health. However, this thesis provides substantial evidence of an important and complicated positive relationship that incontestably exists between physical activity and mental health. Further, the thesis unveils novel hypotheses about the aspects of this relationship, which, provided that they are further explored, could advance and deepen the knowledge-base in the sciences of physical activity and exercise, and in their related fields. Moreover, the thesis elucidates the relevance of the complicated physical activity – mental health relationship in an attempt to argue for recommendations that are more specific regarding the role of physical activity in mental health. Eventually, the role of the investigations presented in this thesis may be only preliminary, but nonetheless they are valuable, because cross-sectional observation of associations and patterns between behaviors and their potential outcomes may materialize in theories, which can induce new investigations that may reveal new findings, leading to better theories. Moreover, throughout these investigations, understanding can be gained about the cognitive and emotional experiences of the individual participating in sport, exercise, or physical activity, and about why and how may psychological benefits follow from these behaviors. 1. Department of Health (2001). Making it happen: a guide to delivering mental health promotion. Retrieved November 17, 2009, from: http://www.dh.gov.uk/en/Publicationsandstatistics/Publications/PublicationsPolicyAndGuidance/DH_4007907. 2. Scully, D., Kremer, J., Meade, M.M., Graham, R., & Dudgeon, K. (1998). Physical exercise and psychological wellbeing: a critical review. British Journal of Sports Medicine, 32, 111-120. 3. Hamer, M., Stamatakis, E., & Steptoe, A. (2008). Dose response relationship between physical activity and mental health: The Scottish Health Survey. British Journal of Sports Medicine. Published Online First: 10 April 2008. doi:10.1136/bjsm.2008.046243. 4. Salmon, P. (2001). Effects of physical exercise on anxiety, depression, and sensitivity to stress: a unifying theory. Clinical PsychologyReview, 21(1), 33-61

Heavy meson production at a low-energy photon collider

A low-energy $\gamma\gamma$ collider has been discussed in the context of a testbed for a $\gamma\gamma$ interaction region at the Next Linear Collider (NLC). We consider the production of heavy mesons at such a testbed using Compton-backscattered photons and demonstrate that their production rivals or exceeds those by BELLE, BABAR or LEP where they are produced indirectly via virtual $\gamma\gamma$ luminosities.Comment: 13 pages, 4 figures. Submitted as a proceeding to the 5$^{th}$ International Workshop on e$^-$e$^-$ Interactions at TeV Energies. To appear in the International Journal of Modern Physics A, World Scientifi

Network Discovery by Generalized Random Walks

We investigate network exploration by random walks defined via stationary and adaptive transition probabilities on large graphs. We derive an exact formula valid for arbitrary graphs and arbitrary walks with stationary transition probabilities (STP), for the average number of discovered edges as function of time. We show that for STP walks site and edge exploration obey the same scaling $\sim n^{\lambda}$ as function of time $n$. Therefore, edge exploration on graphs with many loops is always lagging compared to site exploration, the revealed graph being sparse until almost all nodes have been discovered. We then introduce the Edge Explorer Model, which presents a novel class of adaptive walks, that perform faithful network discovery even on dense networks.Comment: 23 pages, 7 figure

Mágikus árvaság

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Cascading failures in spatially-embedded random networks

Cascading failures constitute an important vulnerability of interconnected systems. Here we focus on the study of such failures on networks in which the connectivity of nodes is constrained by geographical distance. Specifically, we use random geometric graphs as representative examples of such spatial networks, and study the properties of cascading failures on them in the presence of distributed flow. The key finding of this study is that the process of cascading failures is non-self-averaging on spatial networks, and thus, aggregate inferences made from analyzing an ensemble of such networks lead to incorrect conclusions when applied to a single network, no matter how large the network is. We demonstrate that this lack of self-averaging disappears with the introduction of a small fraction of long-range links into the network. We simulate the well studied preemptive node removal strategy for cascade mitigation and show that it is largely ineffective in the case of spatial networks. We introduce an altruistic strategy designed to limit the loss of network nodes in the event of a cascade triggering failure and show that it performs better than the preemptive strategy. Finally, we consider a real-world spatial network viz. a European power transmission network and validate that our findings from the study of random geometric graphs are also borne out by simulations of cascading failures on the empirical network.Comment: 13 pages, 15 figure

A maastrichti deficitmutató a globális válság időszakában = The Maastricht deficit index in the era of global crisis

A globális válságot megelőzően a gazdaságpolitikai viták középpontjában világszerte a költségvetési fegyelem állt. Úgy tűnt, hogy konzervatív fiskális politika mellett elkerülhetőek a „nagy” válságok, az volt az uralkodó vélemény, hogy a folyófizetési mérleg-hiánynak csak annyiban van jelentősége, amennyiben az a kormányzati szektor hiányára vezethető vissza (Lámfalussy [2008]). Az írás öt olyan válságot vizsgál, amely az Európai Unión belül bontakozott ki. A lett, a svéd, a lengyel, a magyar és a francia gazdaság jól példázza, hogy a korábban alulértékelt kockázatok milyen nagy intenzitással tudnak a felszínre törni. Az értekezés öt fő következtetést von le: ad1) Az öt ország közül a költségvetés felelőtlen gazdálkodása csupán egy esetben (magyar példa) volt a válság magja. Elsősorban a magánszektor túlzott eladósodása és a felelőtlen hitelezés felelt a krízis kibontakozásáért. A folyamatban főszerepet játszott a pénzügyi hatóság elégtelen működése. ad2) A globális válság kialakulását megelőzően a gazdaság túlhevülése kedvezőbb költségvetési helyzetet idézett elő. A külső sokk hatására a reálgazdaság többnyire komoly recesszióba süllyedt, ami nagymértékben közrejátszott a fiskális fegyelem elvesztésében. ad3) Nem csupán a felelőtlen hazai hitelezés jelentette a problémák forrását, hanem a hazai kereskedelmi bankok nagyarányú kitettsége a sérülékeny régiók irányába. A globalizáció folyamatával áll összefüggésbe, hogy jelentős volt a válsággal sújtott országok száma, ami a későbbiekben beszűkítette a gazdaságpolitika lehetőségeit (Blanchard-Leigh [2013]). A kockázatok csökkentéséhez hozzájárul a nemzeti pénzügyi hatóságok tevékenységének jobb összehangolása. ad4) A krízisek a piacgazdaság szükséges velejárói (Lámfalussy [2008]). A 2008-as külső sokk előtt a kormányzati erőfeszítések túlzottan is a válságok megelőzésére összpontosítottak, így elveszett a „valós árazás” az üzleti szereplők körében. Ez a viselkedés vezetett el végül a világméretű válsághoz (Rostowski [2010]). ad5) A maastrichti deficitkritérium (illetve általában a fiskális előírások) huzamosabb ideig abba a hitbe ringatták a befektetőket, nincs különösebb ok aggodalomra a pénzügyek területén, hogy azután még nagyobb legyen a kiábrándultság: ez a fejlemény azonban nem feltétlenül jelenti a maastrichti deficitkritérium költség-haszon mérlegének negativitását vagy a jövőben negatív tartományba billenését. A külső sokk után a nemzeti és az uniós gazdaságpolitikai alakítók is élénkebb figyelemmel kísérik a költségvetési folyamatok mellett az egyéb makrogazdasági indikátorokat, illetőleg a pénzügyi szféra szabályozását. A hipotézisek közül a legfontosabbnak az értekezés annak a bizonyítását tekintette, hogy a gazdaságpolitika alakítóinak a fiskális folyamatok és az azokat leképező fiskális mutatók mellett az egyéb makrogazdasági indikátorokat, illetve a pénzügyi szféra szabályozását is élénk figyelemmel kell kísérniük. A gazdaságpolitika megítélése nagyon komplex feladat, a kockázatok értékelése számos problémát vet fel. De még ha ez a feladat sikeresen is megvalósítható, jóvátehetetlenül kevésnek bizonyul, amennyiben a nemzeti hatóságok nem rendelkeznek megfelelő szintű felelősségérzettel

Politikai változások a költségvetési kiigazítások tükrében

A tanulmány 14 európai ország költségvetési konszolidációját tekinti át 1980 és 2014 között. Rövid elméleti kitekintést követően arra keresi a választ, hogy vannak-e negatív hatásai a kiadásoldali költségvetési kiigazításoknak a politikai folytonosságra nézve. Elemzi a konszolidációk legfontosabb vonásait, felhívja a figyelmet a módszertani nehézségekre, illetve azok jelentőségére a végső eredményt tekintve. Arra a következtetésre jut, hogy a költségvetési fegyelem sikeressége nem állítható szembe a politikai sikerességgel. Journal of Economic Literature (JEL) kód: H12, H62, H870

A zenei képességek és a zenei műveltség kutatása

Az ének- és a hangszerjáték a jellemre gyakorolt jótékony hatásának köszönhetően már az ókori iskolákban is jelentős szerephez jutott. Az utóbbi évtizedek képességvizsgálatai, neuropszichológiai kutatásai pedig egyértelműen rámutattak a zenei készségek fontosságára, amelyek fejlesztése nem csupán a személyiség egészére, de más diszciplínákhoz köthető készségekre és képességekre is kedvezően hat

COMPUTER AIDED ANALYSIS OF MEDICAL, ULTRASOUND-ECHOCARDIOGRAPHIC IMAGES

Ultrasound echocardiography is widely used clinical technique, but images obtained using current technology are still processed manually with semi-automated methods. In contrast to this, the newly developed system works in an automated way, first obtaining a series of long and short axes views of the heart synchronised by the ECG in real time, then processing them off-line. After detection of the internal edges of the left ventricle, the system determines the short/long axes areas, diameters, calculates the volume of the left ventricle frame by frame and, based on this, the ejection fraction for each cardiac cycle. The developed system is currently being tested and the results correlate well with data determined by other methods