Aggressive-antisocial boys develop into physically strong young men

The change in handgrip strength, after physical exercise, is moderated by digit ratio (2D:4D): A study among the young adults in Poland

BACKGROUND

The digit ratio (2D:4D), the ratio of the lengths of second (2D) to the fourth (4D) fingers, is a proxy indicator of prenatal androgen exposure. On average, males display lower 2D:4D than females. Previous studies have shown that lower 2D:4D ratios were associated with better sports and physical abilities.

AIM

To assess whether a challenge condition, imposed by intense exercise, could increase handgrip strength (HGS) associated with 2D:4D.

METHODS

This cross-sectional experimental study included 90 healthy young Polish adults (40 males, 50 females). They underwent intense physical exercise, before (7 days) and after which they were measured for HGS and 2D:4D. Height and weight were also measured. Analyses of Covariance were employed to delineate associations.

RESULTS

2D:4D had significant predictive effects on the differences in HGS (DHGS) measured in two occasions, without and after, physical exercises. The lower was the 2D:4D, the higher the DHGS, particularly, for the left hand.

CONCLUSION

The results reconfirmed that the link between prenatal testosterone exposure (indicated by 2D:4D) and physical strength depends on the context, such as a challenged condition.

Outcomes for Hospitalized Aggressive and Violent Patients When Physical Restraints Are Introduced

BACKGROUND

Hospital outcomes among patients acting aggressively or violently have not been extensively studied in the United States.

OBJECTIVES

The aims of the study are to determine rates of physical restraint use among hospitalized patients who are aggressive/violent and to characterize associations with mortality and utilization metrics.

DESIGN/SETTING/PARTICIPANTS

National Inpatient Sample databases from 2016 to 2019 were analyzed with multivariable regression to compare aggressive/violent patients in whom physical restraints were or were not used.

MEASURES

Prevalence of physical restraint use, in-hospital mortality, length of stay, and total hospital charges were measures.

RESULTS

A total of 40,309 hospitalized patients were coded as having aggressive/violent behavior, of whom 4475 (11.1%) were physically restrained. Physically restrained patients were younger (mean age ± standard error, 42.6 ± 0.64 versus 45.7± 0.41; P < 0.01), more frequently male (71.0% versus 65.4%; P < 0.01), and had less comorbidity (Charlson Index score >3: 7.9% versus 12.5%; P < 0.01) than unrestrained patients. Patients with physical restraints had higher odds of in-hospital mortality (adjusted odds ratio, 2.4, confidence interval [CI], 1.0-5.7; P = 0.04) and lower odds of being discharged to home (adjusted odds ratio, 0.46; CI, 0.38-0.56; P < 0.01) compared with unrestrained patients. Longer hospital stays (adjusted mean difference, 4.1 days CI, 2.1-6.0; P < 0.01) and higher hospitalization charges (adjusted mean difference, $16,996; CI, 6883-27,110; P < 0.01) were observed for those who were physically restrained.

CONCLUSIONS

Physically restrained aggressive/violent patients had worse in-hospital outcomes compared with their unrestrained counterparts. Avoiding physical restraints whenever possible should be considered when managing this confrontational yet vulnerable patient population. When restraints are needed, providers must thoughtfully bear in mind heightened risks for worse outcomes.

The evolution of personality disorders: A review of proposals

Personality disorders (PDs) are currently considered dysfunctions. However, personality differences are older than humanity and are ubiquitous in nature, from insects to higher primates. This suggests that a number of evolutionary mechanisms-other than dysfunctions-may be able to maintain stable behavioral variation in the gene pool. First of all, apparently maladaptive traits may actually improve fitness by enabling better survival or successful mating or reproduction, as exemplified by neuroticism, psychopathy, and narcissism. Furthermore, some PDs may harm important biological goals while facilitating others, or may be globally beneficial or detrimental depending on environmental circumstances or body condition. Alternatively, certain traits may form part of life history strategies: Coordinated suites of morphological, physiological and behavioral characters that optimize fitness through alternative routes and respond to selection as a whole. Still others may be vestigial adaptations that are no longer beneficial in present times. Finally, variation may be adaptative in and by itself, as it reduces competition for finite resources. These and other evolutionary mechanisms are reviewed and illustrated through human and non-human examples. Evolutionary theory is the best-substantiated explanatory framework across the life sciences, and may shed light on the question of why harmful personalities exist at all.

The clashing nature of rebelliousness: Nontraditional attitudes and counter-normative behaviors show divergent associations with intelligence

OBJECTIVE

Prior literature indicates that nontraditional attitudes are linked to higher intelligence. However, such attitudes in adolescence often accompany counter-normative, delinquent-type behaviors, which are themselves negatively linked with intelligence. This points to the possibility of suppression in the relationship between intelligence and nontraditional attitudes.

METHOD

We analyzed a large community sample of 17 year olds (N = 3330) with data on intelligence, nontraditional attitudes, and a diverse collection of self- and teacher-reported counter-normative behaviors. Developmental questions for these relationships were examined through cross-sectional comparisons between the adolescents and their parents as well as longitudinal analysis of the adolescent sample across emerging adulthood.

RESULTS

Youth who endorsed nontraditional attitudes had lower school grades, earlier age at first sex, heavier substance use, and were perceived as more oppositional by their teachers. Each of these problem behaviors was inversely related to intelligence. Accordingly, the positive correlation between nontraditional attitudes and intelligence was much weaker in adolescents as compared to their middle-aged parents. Longitudinal analyses revealed that the association between nontraditional attitudes and intelligence strengthens in early adulthood.

CONCLUSIONS

Associations between intelligence and sociopolitical attitudes can be obscured even by seemingly distal psychological characteristics.

Digit ratio (2D:4D) moderates the change in handgrip strength on an aggressive stimulus: A study among Polish young adults

BACKGROUND

The ratio of the lengths of second finger (2D) to the fourth (4D) is a putative indicator of foetal hormonal exposure. The link between 2D:4D and physical strength or sports performance in not consistent. It was suggested that the association of 2D:4D with the sporting and physical ability is better demonstrated in the context of challenge and competition, either real or simulated. However the evidence is limited to a few studies till date.

AIM

The objective of this study was to assess whether an aggressive video show could increase muscular strength and if 2D:4D moderated such increase.

STUDY DESIGN

We compared outcome measures in two experimental conditions.

OUTCOME MEASURES

Lengths of second (2D) and fourth (4D) digits and their ratio (2D:4D) for both hands, height and weight, handgrip strength of both hands.

SUBJECTS

250 healthy young adults (76 female).

RESULTS

The mean left-, right- and average HGS values increased after aggressive video watching than after control blank screen show. The increase was higher in females compared to males. The increase was higher among the individuals with lower 2D:4D, more clearly among females.

CONCLUSIONS

The 2D:4D correlated negatively with HGS after exposure to challenge condition and this relationship is pronounced in females than males. Thus there is link between prenatal androgenisation and enhanced physical power in challenge situation.

Handgrip Strength as a Darwinian Fitness Indicator in Men

Handgrip strength (HGS) is a robust measure of overall muscular strength and function, and has long been predictive of a multitude of health factors and physical outcomes for both men and women. The fact that HGS represents such a ubiquitous measure of health and vitality may reflect the significance of this trait during human evolution. This trait is also highly sexually dimorphic due to influences of androgenic hormones and fat-free body mass, suggesting that it has been further elaborated through sexual selection. Consistent with this view, research within evolutionary psychology and related fields has documented distinct relationships between HGS and measures of social and sexual behavior, especially in men. Here, we review studies across different societies and cultural contexts showing that male HGS predicts measures of aggression and social dominance, perceived formidability, male-typical body morphology and movement, courtship display, physical attractiveness, and sexual behavior and reproductive fitness. These findings underscore the value of including HGS as an independent measure within studies examining human sexual selection, and corroborate existing research suggesting that specific features of physical strength have and continue to be under positive directional selection in men.

PSYCHOLOGICAL AND SOCIODEMOGRAPHIC CHARACTERISTICS AND DEVELOPMENT OF PHYSICAL EXERCISE DEPENDENCE

ABSTRACT Introduction: Excessive physical exercise combined with certain psychic and sociodemographic factors can lead to dependence. Objective: To examine which factors lead to the emergence of exercise dependence. Methods: Sample consisted of 103 men (mean age 27.3 years, SD 6.127) who performed exercises at gyms at least three times a week in the last year or more in Novi Pazar, Sjenica, Raska and Tutin, Serbia. Participants completed questionnaires and took appropriate tests. Results: Our results showed that there is no association between exercise dependence and financial status, number of siblings, level of education, family stability, health, and medication use among the interviewees. However, it was found that the degree of exercise dependence is associated with marital status and problems with the law. Regression analysis showed that body dysmorphia, body mass index and aggressiveness are better predictors of exercise dependence. Conclusion: People whose self-perception is dismorphic have lower self-esteem, and exercise in gyms to improve their physical appearance. If we consider other characteristics, such as unfavorable BMI, problems with the lаw and being single, it is hardly surprising these individuals cross the line between healthy exercise and exercise dependence. An important finding is that aggressiveness and exercise dependence are related to problems with the law due to aggression, and body dysmorphia. Level of Evidence; Diagnostic studies - Investigating a diagnostic test.

Physical Strength as a Cue to Dominance

We investigate both similarities and differences between dominance and strength judgments using a data-driven approach. First, we created statistical face shape models of judgments of both dominance and physical strength. The resulting faces representing dominance and strength were highly similar, and participants were at chance in discriminating faces generated by the two models. Second, although the models are highly correlated, it is possible to create a model that captures their differences. This model generates faces that vary from dominant-yet-physically weak to nondominant-yet-physically strong. Participants were able to identify the difference in strength between the physically strong-yet-nondominant faces and the physically weak-yet-dominant faces. However, this was not the case for identifying dominance. These results suggest that representations of social dominance and physical strength are highly similar, and that strength is used as a cue for dominance more than dominance is used as a cue for strength.

Digit ratio (2D:4D), testosterone, cortisol, aggression, personality and hand-grip strength: Evidence for prenatal effects on strength

BACKGROUND

Digit ratio (2D:4D) is a putative marker for prenatal testosterone and is correlated with performance in many sports. Low 2D:4D has been linked to strength but the evidence is mixed and strength is also influenced by mass, testosterone, and behavioural factors. It has been hypothesised that the 2D:4D-strength correlation may be strongest in challenge conditions when short-term changes occur in steroid hormones.

AIMS

We tested this suggestion in men.

STUDY DESIGN

We used a cross-over study design with a challenge (an aggressive video of rugby tackles) and control (a blank screen) condition.

SUBJECTS

89 healthy men.

OUTCOME MEASURES

Finger lengths (2nd and 4th for both hands), hand-grip strength (HGS), testosterone (T), cortisol (C), aggression (Buss-Perry Aggression Questionnaire) and personality type (Ten Item Personality Measure). In both conditions participants provided saliva samples (for hormone assays).

RESULTS

In the challenge condition there was a highly significant increase in HGS, and modest changes in T, physical aggression and emotional stability. HGS correlated negatively with left hand 2D:4D. In a multiple regression, left hand 2D:4D was negatively related to HGS and emotional stability was positively related to HGS. In the control condition HGS was not correlated with 2D:4D. In a multiple regression, BMI, physical aggression, and emotional stability were significantly related to HGS.

CONCLUSIONS

2D:4D is a negative correlate of strength in challenge situations. This finding may in part explain associations between 2D:4D and sports performance.