Effects of lunar phases on short-term,explosive physical performance among young trained athletes

Beliefs that lunar phases affect human physiology started in ancient times. Research has recently revealed that a physical fitness index increased in sedentary students at the new moon (NM) and full moon (FM) compared to other moon phases. However, the effect of lunar cycle (moon illumination and gravitational pull) on physical performance in athletes was not examined. Therefore, this study aimed to evaluate whether short-term explosive performance can be influenced by the different phases of the lunar cycle. Fourteen young male Taekwondo athletes (age: 16.9 ± 0.7 years, height: 159.7 ± 50.6 cm, body mass: 62.85 ± 7.84 kg) performed the following tests to assess the explosive physical performance during the different phases of the lunar cycle (NM, FQ (first quarter), FM, and LQ (last quarter)): maximal isometric manual contraction (dominant hand (MIMCD) and non-dominant hand (MIMCND)), maximal back isometric contraction (MBIC), squat jump (SJ), countermovement jump (CMJ), and 10-m sprint (10 m). The testing sessions during the different moon phases were performed in a counterbalanced order. The order of tests remained the same (MIMCD, MIMCND, MBIC, SJ, CMJ, and 10 m), and all sessions were performed in the evening (6:00 to 8:00 p.m.) on the first day of each evaluated lunar phase. Each parameter was measured over two consecutive lunar months in the calendar. Analysis of variance tests showed that there was no significant effect of lunar cycle on all explosive test measures, p > 0.05. Our results failed to identify any effect of lunar phase on evening explosive performance (mainly involving phosphagen pathway-based efforts) among young trained athletes. Therefore, it appears that moon phase/illumination does not affect short-term physical performance in young trained adolescents.     

Physiological effects of the lunar cycle on the spawning of a coral reef fish,Abudefduf Vaigiensis: in vivo and in vitro trait

The aim of the present study was to investigate the lunar cycle effects of the spawning of Audefduf vaigiensis through in vivo and in vitro analysis. For this purpose, the indices of GSI, serum levels of sex steroids, including testosterone (T), 17α-hydroxyprogesterone (OHP), 17α, 20β-dihydroxyprogesterone (DHP), and 11-keto-testosterone (11-KT) as well as the germinal vesicle breakdown (GVBD) were measured. The sampling pattern was weekly, based on the moon cycles as the new moon (NM), the first quarter (FQ), the full moon (FM), and the last quarter (LQ). In females, the highest in vivo values of the GSI index were obtained in FQ and LQ, and in males, this value was significantly higher in LQ than NM. The highest in vivo level of OHP in females was observed in FQ, whereas in males was obtained in FM. In both sexes, the in vivo serum levels of DHP were obtained in LQ. In males, the level of 11-KT were at the peak in NM. In vitro analysis showed the highest rate of GVBD in LQ. Moreover, the in vitro levels of T, OHP, and DHP were significantly higher in LQ compare to NM in both sexes. However, in males, the in vitro levels of 11-KT was significantly higher in NM than LQ. These cyclical changes obtained from in vivo plasma steroid hormones and in vitro data on GVBD suggested that lunar periodicity is a major external regulator that synchronized ovarian and testicular activity of A. vaigiensis with emphasis on spawning phenomenon.

     

Time of day affects heart rate recovery and variability after maximal exercise in pre-hypertensive men

ABSTRACT

Previous literature suggests that human behaviour and physiology are somehow altered by the moon-cycle, with particular emphasis on poorer sleep quality and increased aggressive behaviour during full moon. The latter variables can negatively impact athletes’ recovery and increase the likelihood of injury resulting from collision with another athlete. Therefore, the current study aimed to investigate the association between the lunar cycle and injury risk in professional football players (soccer). We monitored injuries and player exposure in the premier professional league in Qatar during four consecutive seasons (2013–2014 through 2016–2017). Acute (sudden-onset traumatic) injuries (n = 1184; 587 from contact with another player and 597 without player contact) recorded during matches and training were classified according to the lunar cycle characteristics on the date of injury: (i) moon illumination, (ii) lunar distance from earth and (iii) tidal coefficient, acquired from the lunar calendar and tide tables. We used a Poisson regression model to examine the relationship between injury risk and lunar cycle characteristics. We did not detect any association between injury risk and moon illumination, earth-to-moon distance or tidal coefficient, not for all acute injuries, nor for contact and non-contact injuries when examined separately. The findings suggest that the full moon or new moon or the gravitational pull have no effect on football injuries. Thus, organisers need not consult moon or tide tables when planning future event schedules.     

Full moon and crime.

The incidence of crimes reported to three police stations in different towns (one rural, one urban, one industrial) was studied to see if it varied with the day of the lunar cycle. The period of the study covered 1978-82. The incidence of crimes committed on full moon days was much higher than on all other days, new moon days, and seventh days after the full moon and new moon. A small peak in the incidence of crimes was observed on new moon days, but this was not significant when compared with crimes committed on other days. The incidence of crimes on equinox and solstice days did not differ significantly from those on other days, suggesting that the sun probably does not influence the incidence of crime. The increased incidence of crimes on full moon days may be due to "human tidal waves" caused by the gravitational pull of the moon.     

Apparent semi-lunar spawning rhythmicity in a brackish cardinalfish

The purpose of the present study was to examine the lunar-related spawning rhythmicity of the amboina cardinalfish Apogon amboinensis, which is a euryhaline species inhabiting mangrove creeks in the Indo-Pacific area. During the reproductive season, the gonado-somatic index increased towards and peaked within a week of the first and last quarter moon. Histological observations of the ovaries also showed development of yolk-laden oocytes towards the first and last quarter moon; postovulatory follicles, an indicator of spawning, appeared around these lunar phases. Fish with immature oocytes in the ovary were also collected in the same lunar phases, suggesting that at least two fish populations with different oocyte development stages exist at any given time. The levels of two steroid hormones secreted from the ovarian pieces into a culture medium with human chorionic gonadotropin were measured using enzyme-linked immunosorbent assay (ELISA). The level of oestradiol-17β increased around the new and full moon periods. On the other hand, 17α,20β-dihydroxy-4-pregnen-3-one levels increased around the first and last quarter moon, suggesting that the fish are actively undergoing vitellogenesis and final oocyte maturation around the respective lunar phase. These results suggest that with the 1 month ovarian development process, A . amboinensis exhibits a semi-lunar spawning pattern with peaks around the first and last quarter moon. When A . amboinensis were reared under laboratory conditions without the tidal stimuli, mouth-brooding was initiated in 13 of 20 males within a week of the first and last quarter moon. The possibility of a lunar-related endogenous rhythm in A . amboinensis is discussed.     

Lunar cycle and psychiatric hospital admissions for schizophrenia: new findings from Henan province,China

ABSTRACT

Objective: Findings on the effect of the lunar cycle on mental illness are conflicting. We investigated the association between the lunar cycle and a number of psychiatric presentations of schizophrenia and determined which subtypes were susceptible to lunar phases.

Methods: We evaluated 13,067 patients admitted to Zhumadian Psychiatric Hospital between January 1, 2012, and December 31, 2017 (73 lunar cycles). Patients were retrospectively assigned to lunar phase based on their admission date: new moon +/? 1 day, first quarter +/? 1 day, full moon +/? 1 day, and third quarter +/? 1 day. The International Statistical Classification of Diseases, 10th revision (ICD-10), was used for diagnosis. We used a Chi-squared goodness of fit test to evaluate the distribution of admissions across the lunar phase and R*C Chi-squared tests to compare age, sex, birth season, and clinical subtype distributions by phase. We used multiple logistic regression to further identify the relationship between clinical subtype and lunar phase.

Results: Psychiatric admissions for schizophrenia varied significantly across the lunar cycle (χ² = 36.400, p< .0001), peaking in the first quarter, followed by the full moon, and lowest at the new moon. Using unspecified schizophrenia (F20.9) as reference, people with paranoid schizophrenia (F20.0) were more likely to be admitted in the full moon than in other phases (odds ratio: 1.157, 95% confidence interval: 1.040–1.286) (p < .05); other subtypes showed no admission differences during the four lunar phases (p > .05).

Conclusions: Psychiatric admissions for schizophrenia show lunar periodicities. People with schizophrenia tend to be stable in the new moon, but their condition is easily aggravated during the first quarter and full moon. Patients with paranoid schizophrenia are more susceptible to deterioration at the full moon, so merit more attention and care from communities, families, and hospitals.     

Integrated use of moon and magnetic compasses by the heart-and-dart moth,Agrotis exclamationis

Use of the moon as a compass during migration appears difficult due to the complexity of the moon's change in azimuth during the lunar month. These apparent difficulties would be eased if the moon's position were calibrated at intervals against a constant reference source, such as the geomagnetic field. Yet, until now, no animal has been shown to integrate moon and magnetic compasses for orientation. In this study, light-traps were used on 15 nights during a lunar month to obtain samples of heart-and-dart moths, Agrotis exclamationis, characterized by a preference to fly ‘toward’ (i.e.±90°) the moon's azimuth. The compass orientation of each sample was then tested in normal and reversed geomagnetic fields, out of sight of the moon. Compass orientation relative to the ambient magnetic field coincided with the compass bearing of the moon at the time of capture. Directional preference changed during the lunar month in a way that tracked the change in the moon's azimuth. It is concluded that moths use the geomagnetic field to calibrate a moon compass.     

Novel perspectives on the influence of the lunar cycle on the timing of full-term human births

ABSTRACT

It is claimed by some that the number of births occurring at the time of the full moon is greater than other phases of the lunar cycle; however, many publications fail to substantiate the claim leading to the conclusion it is myth. We tested using a novel approach the null hypotheses: (i) human birth is not lunar cycle-dependent and (ii) the number of births occurring at or around the time of the full moon is not different from the number occurring at the time of the other phases of the lunar cycle. We reviewed the birth records from 1 January 1996 to 16 March 2007 of the obstetric department of our hospital, which was then located in a relatively undeveloped area of Fukutsu city in Fukuoka Prefecture of southern Japan. A total of 1507 births satisfied all inclusion criteria, among others, being full-term and following spontaneously initiated labor. When the birth data were analyzed as done by other investigators, i.e. total number of births per lunar day, lunar phase was not found to be influential. However, more detailed analyses on the subset of babies born specifically during the nighttime hours (N = 362) revealed the number of births varied in relation specifically to the changing amount of moonlight during the nighttime at different stages of the lunar cycle, with highest number of births at or around the time of the full moon. In contrast, analyses on the subset of babies born specifically during the daytime hours (N = 377) revealed the number of births varied in relation specifically to the changing amount moonlight during the daytime at different stages of the lunar cycle, with the highest number of births at or around the time of the new moon. The initiation and culmination of human birth are typically a nocturnal process. The findings of this investigation are consistent with the hypothesis natural nighttime parturition is influenced by lunar phase, particularly the full moon, and, thus, they are consistent with the belief the moon exerts an affect upon the timing of human birth. We speculate the long-hold belief of the association between birth and lunar phase may be based on historical observations that in the absence of artificial light at night nocturnal births occurred in elevated number when the full moon brightly illuminated the nighttime sky.     

江苏通州杨树枝把诱集棉铃虫成虫的数量与月相的关系

经常规及圆形统计分析 ,结果表明江苏省通州市 1 973～ 2 0 0 0年棉铃虫杨树枝把诱蛾量 (相对量 ,%)受到月相的显著影响。单日比较 ,农历 1 5日蛾量最高 ,3 0日最低 ,前者是后者的 4倍。按 3d时间分段 ,1 3～ 1 5日蛾量最高 ,2 2～ 2 4日最低。按旬分 ,中旬最高 ,下旬最低。按半月分 ,上半月高于下半月。以上差异均达极显著水准 (P <0 0 1 )。圆形分析表明全月蛾峰集中角对应时间为 1 1日 1 1时 3 4分。这些日期都在月满稍前。     

Variations in the locomotor activity of the Mexican wolf (Canis lupus baileyi) respect to moon periodicity: a study in an outdoor enclosure

It is assumed that the response of the regulatory system of mammal activity depends on the changes in light intensity throughout the 24-h cycle. The aim of this study was to determine whether the moon luminosity cycle exerts an effect on the locomotor activity of the Mexican wolf (C. lupus baileyi). Data collection was carried out with the actimetry, of 11 individuals were analyzed using ANOVA to determine the effect of the lunar cycle. Significant differences were encountered between moon phases (p = 0.001), with a decrement of activity during new and full moon. However, effects were dependent also on the age of the individuals and the daylight period. On the other hand, it is a possible regulation of the activity pattern by the effect of lunar periodicity. This periodicity needs a more detailed examination to determine its adaptive function.     

Perception and possible utilization of moonlight intensity for reproductive activities in a lunar-synchronized spawner, the golden rabbitfish

Rabbitfishes are known to spawn synchronously around the species-specific lunar phase. It is considered that they perceive and utilize cues from the moon in order to be synchronized gonadal development and spawning with the lunar cycle. Using the golden rabbitfish, Siganus guttatus, which spawns synchronously around the first quarter moon during the reproductive season, we measured the fluctuation of melatonin levels and examined the response of the fish to moonlight intensity. Daily fluctuation of melatonin concentration in the blood of golden rabbitfish showed low levels during daytime and high levels during night-time, suggesting that melatonin functions in the perception and utilization of photoperiod. Plasma melatonin concentration at the new moon was higher than that at the full moon. When the fish were exposed to moonlight at midnight of the both moon phases, the melatonin concentrations decreased to the control levels. These results show that the fish possibly perceive moonlight intensity and plasma melatonin fluctuates according to 'lightness' at a point of night. At the first spawning period (experiment was started one month before the spawning), the fish reared under natural conditions spawned at the expected spawning dates, whereas the fish reared under the constant darkness and lightness of night did not spawn. At the second spawning period (experiment was started 2 weeks before the spawning), the fish reared under the conditions of natural and constant darkness of night spawned but not that of constant lightness of night. It is possible that night conditions are related to synchronous gonadal development and spawning in the golden rabbitfish.     

Effects of lunar cycles on Artemia density in hypersaline environments

The effects of lunar cycles are known to have an influence, although not yet clear, on the behavior of aquatic organisms. A study was conducted in two different locations (Manaure, Guajira and Chengue, Magdalena, Caribbean coast, Colombia) during July and August, 1997 and November, 1998 to determine the effects of medium term cycles (lunar cycles) on the presence of Artemia franciscana (Crustacea: Anostraca) density. Samples were collected every 4 h from each of 20 fixed stations in a salt production pond during a 24-h sampling period at the peak of the four lunar phases. The data were analyzed using a mixed ANOVA model, setting lunar phases and sampling time intervals as fixed effects, station as the random effect and density as the dependent variable. No significant difference was determined between increasing and decreasing moon. Artemia density was not significantly (P>0.05) higher during new moon compared to full moon. The influence of temperature over Artemia sampling density was clearly noticed, and was a shading factor over the possible effects of any particular lunar phase over Artemia density at any particular sampling time.     

Temporal activity patterns of North China leopards and their prey in response to moonlight and habitat factors

The nocturnal activities of predators and prey are influenced by several factors, including physiological adaptations, habitat quality and, we suspect, corresponds to changes in brightness of moonlight according to moon phase. In this study, we used a dataset from 102 camera traps to explore which factors are related to the activity pattern of North China leopards (Panthera pardus japonensis) in Shanxi Tieqiaoshan Provincial Nature Reserve (TPNR), China. We found that nocturnal activities of leopards were irregular during four different lunar phases, and while not strictly lunar philic or lunar phobic, their temporal activity was highest during the brighter moon phases (especially the last quarter) and lower during the new moon phase. On the contrary, roe deer (Capreolus pygargus) exhibited lunar philic activity, while wild boar (Sus scrofa) and tolai hare (Lepus tolai) were evidently lunar phobic, with high and low temporal activity during the full moon, respectively. In terms of temporal overlap, there was positive overlap between leopards and their prey species, including roe deer and tolai hare, while leopard activity did not dip to the same low level of wild boar during the full moon phase. Human activities also more influenced the temporal activity of leopards and wild boar than other species investigated. Generally, our results suggested that besides moonlight risk index (MRI), cloud cover and season have diverse effects on leopard and prey nocturnal activity. Finally, distinct daytime and nighttime habitats were identified, with leopards, wild boar, and tolai hare all using lower elevations at night and higher elevations during the day, while leopards and roe deer were closer to secondary roads during the day than at night.     

Sex differences in the effects of the moon on ischemic stroke incidence: new findings from Beijing,China

ABSTRACT

Stroke is a major cause of death and disability in China, and no therapies have proven effective to prevent it. Popular belief holds that the lunar cycle affects human physiology, behavior, and health. The aim of our study is to determine whether the lunar cycle impacts the incidence of stroke subtypes [intracerebral hemorrhage (ICH), transient ischemic attack (TIA) and ischemic stroke (IS)]. We retrospectively extracted the discharge registry data of all patients with first-ever acute stroke hospitalized in the affiliated hospital of Beijing University of Traditional Chinese Medicine during 2002–2015. The onset times of stroke were assigned to four primary lunar phases based on NASA definitions. Chi-square tests and multiple logistic regression analyses were used to estimate the association between the lunar cycle and stroke incidence with adjustment for age, sex and season. A total of 5,965 patients with stroke (4,909 admissions for ischemic stroke IS, 754 admissions for ICH, and 302 admissions for TIA) were evaluated in our study. Subgroup analysis indicated that the admission rates of different sexes for IS tended to have opposite variation during the four moon phases. More female patients were admitted during the new moon than in the first and third quarters, while fewer male patients were admitted during the new moon than in the first and third quarters (χ2 = 15.589, P = .001). Multiple logistic regression analyses revealed that men were more likely to be admitted for IS in the first quarter than during the new moon (odds ratio [OR] = 1.252, 95% confidence interval [CI] = 1.076–1.456) (P = .004), and a corresponding trend was also identified for the third quarter (OR = 1.235, 95% CI = 1.062–1.437) (P = .006). No significant gender differences were shown in ICH or TIA. No sex difference is obvious during the full moon. Moon phases seem to affect both genders, but in very different ways. It seems that the new moon is a protective factor for male ischemic stroke patients and a risk factor for female ones. Woman tends to be more vulnerable than ever at the new moon, so deserves more attention and care. The mechanisms underlying this observation are worth studying further.     

Moonlighting? - Consequences of lunar cues on anuran reproductive activity

While the influence of environmental variables, particularly temperature and rainfall, on the breeding behavior of amphibians is widely recognized, relatively few studies have addressed how the moon affects amphibian behavior. Yet, the lunar cycle provides several rhythmic temporal cues that animals could use to time important group events such as spawning, and the substantial changes in light levels associated with the different moon phases may also affect the behavior of nocturnal frogs. Using seven years of field observation data, we tested for lunar effects on the reproductive activity of male and female Eastern Gray Treefrogs (Hyla versicolor). We found that chorusing and breeding activity was statistically more likely to occur around the first quarter of the moon and during intermediately bright nights, but that reproductive activity also occurred during various other times during the lunar cycle. We discuss these findings in relation to the two main hypotheses of lunar effects on animals: predator avoidance and temporal synchronization of breeding.     

Changes in circadian parameters of humbug damselfish,Dascyllus aruanus according to lunar phase shifts in Micronesia

The objectives of this study were to test the nighttime effects of the lunar phase on circadian rhythm in the humbug damselfish, Dascyllus aruanus. We measured moonlight intensities at eight different phases across the lunar cycle. At each lunar phase, the circadian rhythm was evaluated by measuring the clock genes cryptochrome 1 and period 2. In addition, we measured arylalkylamine N-acetyltransferase 2 (AANAT2), melatonin and melatonin receptor 1 (MT-R1). The moonlight intensity was highest at full moon and lowest during the waning crescent. Clock gene expression was highest during the full moon compared to the other phases. By contrast, the plasma concentrations of AANAT2 and melatonin and the MT-R1 mRNA expression were highest during the full moon phase. Our results suggest that moonlight affects circadian rhythm patterns in the humbug damselfish. There is a need to investigate potential other physiological effects of lunar phase shifts.     

Offspring sex ratio in sheep,cattle, goats and pigs: influence of season and lunar phase at conception

This study assessed the relationship between season and lunar phase at conception on offspring sex ratio of four livestock species (sheep, cattle, goats and pigs). The sex of 66,830 lambs (1995–2015); 25,546 calves (2011–2015); 5671 kids (2002–2007) and 1916 piglets was recorded. Moon phases were categorized as either new moon, crescent moon, full moon or decrescent moon. Sex ratio, expressed as proportion of males (males/males + females), was tested against the expected value of 1:1. In sheep, offspring sex ratio and lunar phase were not correlated; season had a significant (p = 0.002) effect on offspring sex ratio. The proportion of males born of spring and winter matings was significantly higher than it was among offspring born of summer (p < 0.05) or autumn (p < 0.01) conceptions. Offspring sex ratios in spring (p < 0.05), autumn (p < 0.01) and winter (p < 0.05) differed significantly from the expected. In cattle, moon phase and season did not affect the offspring sex ratio; however, the interaction effect was highly significant (p = 0.001). The overall piglet sex ratio (0.522), and the sex ratios among piglets conceived during a crescent moon and those conceived in summer differed significantly (p < 0.05) from 1:1. Research including additional factors such as hormonal treatments prior to insemination, food availability, weather and maternal and paternal factors might provide the underlying reasons for the effects of season and moon phase on offspring sex ratio in some livestock species.     

The rate of spontaneous epistaxis is not linked to the lunar cycle but shows seasonal variations

Since 50–60% of the human body consists of water, the physiology of blood circulation might be affected by a full moon differently than during other days of the month. This study analyzed a potential association among lunar phases, seasonal variations, and the rate of spontaneous epistaxis. Consecutive admissions solely for spontaneous epistaxis to an otolaryngology emergency room of a single medical center during 1 year were evaluated. The applied tests failed to show changes of admissions during different lunar phases. According to multiple comparisons, admissions were significantly less frequent during the summer months, similar to findings from other countries of the northern hemisphere with varying climates, suggesting an influence of circannual rhythms rather than of environmental conditions.     

Lunar influences in the diet habits and selectivity of larval clingfish Gobiesox marmoratus

The influence of the lunar cycle on the feeding habits, feeding success and selectivity was tested in situ on larval stages of the clingfish Gobiesox marmoratus (Gobiesocidae). Gobiesox marmoratus larvae and their prey were collected in the water column during the lunar cycle in austral spring 2015 and 2016, in shallow waters (<30 m depth) of El Quisco, central Chile. Feeding incidence was high (80–100%) throughout the moon cycle. The diet was composed of 32 prey items, being gastropod larvae and invertebrate eggs the most important. Prey composition varied among lunar phases with the lowest prey richness during new moon. During 2016, G. marmoratus larvae ingested the lowest number, but the largest prey during new moon. In spring 2015, there were no significant changes in the abundance of each prey taxon in the water column among moon phases, but in spring 2016 there were significant differences in the abundance of cypris and copepod nauplii, particularly between full and new moon. Feeding selectivity index showed that gastropod larvae were positively selected throughout the lunar cycle during spring 2015. In spring 2016, invertebrate eggs were selectively ingested in full moon and third quarter, but at a new moon G. marmoratus larvae selected gastropod larvae. Mean temperature of the water column and its vertical gradient and nocturnal cloud cover influences the feeding success of larval G. marmoratus. Lunar illumination favoured only an increase of richness of prey items. Therefore, nocturnal cloud cover precludes a greater influence of lunar illumination in the larval trophic ecology of this crypto-benthic fish.