International Physiology

Stress is an indispensable aspect of our daily life. Individual of Type-A or type-B personalityrespond to the same stressful event differently. Aim of this study was to assess theimpact of stress and personality on Heart Rate Variability (HRV) in prehypertensives. 115 participants were categorized into type-A and type-B personalities based on modified jenkin’s questionarie as normotensives and prehypertensives based on their blood pressure recordings. During the mental stress, the TP, HF nu, HF LF were decreased (p<0.05). The LF nu and LF/HF ratio were increased (p<0.05), which was statistically significant, indicating an increased sympathetic activity and decreased parasympathetic activity in type-A prehypertensives. We can conclude that the effect of mental stress on HRV in type –A prehypertensives was much more than type-B personalities. This proves that type-A prehypertensives have a hyperactive sympathetic system and are more susceptible to stress than type-B individuals.

Keywords: Type-A Personality; Type-B Personality; Prehypertension, Heart Rate Variability; Stress.   

 Anemia is a major health problem in developing countries. Adolescent females are at the higher risk of developing anemia because of their greater physiological demand and combined with increase menstrual losses and poor dietary intake. Decrease hemoglobin level may lead to decrease attentiveness and low neural metabolic activity. Objectives: To observe the effect of anemia on audio and visual reaction time in adolescent females and to find out correlation between hemoglobin and reaction time. Material and Methods: The study was conducted in the department of physiology, Jhalawar medical college, Jhalawar. Adolescent females between 17-19 years of age and belonging to similar socio-economic status were recruited for the study. After hemoglobin estimation by Sysmex XN 1000 auto analyzer . Two groups, group-I (n=35) with hemoglobin level ≥12 gm/dl and group-II (n=35) with hemoglobin level <12 gm/dl were made.Visual reaction time and auditory reaction time were measured by using reaction time software in computer programming language Visual Basic 6.0. Results: Significant difference in visual reaction time (VRT) and auditory reaction time (ART) was found between two groups. The mean VRT in group I was185.7143 ± 14.4070 and in group II was 221.1429 ± 20.5471.The mean ART in group I was 152.0000 ± 14.9115 and in group II was 172.5714 ± 15.9674 .VRT and ART shows negative correlation with hemoglobin(rValue-0.619 and - 0.401 respectively), which was significant. Conclusion: Both visual reaction time and auditory reaction time were significantly increased in anemic adolescent females. Anemia may be responsible for the impairment of reaction time (sensori motor function) in females of the adolescent age group 17-19 years.

Keywords: Anemia; Reaction Time; Adolescent Females.

 Background: Judo is a dynamic and tremendous combat sport that demands both physical prowess and great mental discipline. Maximal muscle strength is ultimate strength value under static conditions. Flexibility is defined as the maximal passive physiological range of motion in a given joint movement. Agility is the ability to move the body in order to change directions quickly and accurately. Objective: To compare muscular strength, flexibility and agility levels of judo players with age matched sedentary first year MBBS students and understand the effect of training on these parameters. Material and methods: For this study, 31 judo players and 31 sedentary MBBS students as controls were included. Muscular strength was assessed by 1 repetition maximum (1RM) Bench press and bench squat, flexibility by sit and reach tester and agility by side step test. Students unpaired ‘t’ test used for analysis. Results: Unpaired t-test With p<0.05 significance was applied for values expressed as Mean ± SD, all the parameters muscle strength, flexibility and agility levels were higher in judo player group with statistically significant difference. Conclusion: There is significant effect seen due to training on the parameters in judo players which can be understood better and help in formulating techniques during training sessions to get better results from players.

Keywords: Muscle Strength; Repetition Maximum; Flexibility; Agility; Side Step Test; Sit and Reach Test.

 Background: Cognitive Evoked Potential components are depend on mental attention of subject which are related with cognition, memory. Aims and Objectives: The purpose of study is comparison of properties of event related potential in athletes and cricket players. Material and Methods: Total 60 athletes (15-25 years), from district sports academy, who are regularly practicing from more than 3 years having physical activity 5-7 hrs per week. We have taken 60 healthy age match volunteer controls having physical activity less than 5 hrs per week. Both control & athletes don’t have any abnormality of auditory, neurological problem. Evoked potential, P300 response was recorded using standard auditory oddball paradigm by Rmsemg Ep II machine. All participants received 3-minute conventional, eyes-closed, awake, rehearsal by placing headphone over ears after 5-minute habituation to experimental environment. 2 tones were used as stimulus, frequent low pitch tone & rare high pitch tone. Subjects were instructed to ignore common low pitch tones and raise finger of dominant hand each time when rare high pitch tone occurred. P300 response was recorded from vertex (Cz) in response to stimuli. The mean value of latency, amplitude was further analyzed using anovatest to establish whether statistical differences existed between controls and athletes for ERP. Results: ERP (P300) latency was significantly less and amplitude was significantly more in athletes in athletes as compared to controls having p value >0.001 (highly significant).

Keywords: Event Related Potential; P300; electroencephalogram (EEG)

Background: Hypertension is one of the most rampant diseases in the world. Many genes are responsible for expression of normal blood pressure. This hints a probable role of family history in the development of hypertension, which we are trying to assess in this study. As BP is regulated by autonomic nervous system (ANS), altered activity of ANS suggestsa greater risk of development of hypertension. ANS is assessed by HRV which is a simple and noninvasive test. HRV represents the total amount of fluctuations in heart rate and R-R interval measured by time domain and frequency domain methods. Deep breathing causes stimulation of parasympathetic system by activating the stretch receptors. Hence HRV during deep breathing gives an idea about the activity of parasympathetic nervous system. Materials & Methods: We studied 67 subjects with or without family history of hypertension. BP and HRV of the two groups were compared,during normal breathing and deep breathing. Results: Two groups did not show significant discrepancy in BP and HRV at rest. However, HRV by time domain analysis (RMSSD and pNN50) showed a lower value in study group compared to control group in which RMSSD values were significantly less during deep breathing. This indicates that although the recorded BP of offsprings of hypertensive parents show a normal value at rest, they are havinga distorted ANS activity which is not manifested at rest. The low parasympathetic activity present in them became evident by the autonomic excitatory maneuver i.e. deep breathing. Conclusion: From this study it is apparentthat the wards of hypertensive parents are more prone to develop hypertension.

Keywords: Blood Pressure; Deep Breathing; Heart Rate Variability.   

 Background: Pregnancy is a physiological condition associated with adaptive changes in the maternal hemodynamics and cardiovascular system. Autonomic nervous system plays a central role in this adaptation to the various needs of pregnancy. One of the well-known complication, that occurs commonly during pregnancy is pregnancy induced hypertension (PIH)/preeclampsia (PE). Impairment of autonomic functions has been suggested as one of the cause of pregnancy induced hypertension. Vascular reactivity is defined as the responsiveness of a blood vessel to a specific stimulus. Blood pressure (BP) reactivity to the cold pressor test (CPT) has been suggested as a one of the predictor of hypertension. Materials and Methods: A total of 225 pregnant females with gestation age of 7-8 weeks as per the ultra-sonographic reports were recruited in the study and were divided into 3 groups 18-23 years (n=132), 24-29 years (n= 78) and 30-35 years (n=15). Observations and Results: The baseline SBP were 102.90 ± 11.95 mm Hg, 103.23 ±12.58 mm Hg, and 113.23 ± 12.53 mm Hg respectively in different age groups. The baseline DBP was 63.90 ± 9.20 mm Hg, 65.78 ± 10.92 mm Hg and 71.33 ± 9.17 mm Hg. It was observed that resting SBP and DBP increased with maternal age. The change in SBP and DBP during CPT was 12.02 ± 11.56 mm Hg and 12.12 ± 10.57 mm Hg in 18-23 years of age, 13.76 ± 16.22 mm Hg and 13.15 ± 14.99 mm Hg in 24-29 years of age, 12 ± 14.62 mm Hg in 30-35 years of age. This shows that there is more change in SBP and DBP till the age of 25-29 years which further decreased in 30 -35 years of age group. Conclusion: Thus there is an ambiguous relation of sympathetic vascular reactivity with age in pregnancy

Keywords: Pregnancy Induced Hypertension; Autonomic Nervous System; Vascular Reactivity; Cold Pressor Test.