Shalini Verma

Physical and balance performance following exercise induced muscle damage in male soccer players

[Purpose] The present study aimed to determine the changes in physical and balance performance following exercise-induced muscle damage using a sport-specific protocol. [Subjects and Methods] Fifteen collegiate soccer players were asked to perform a sport-specific sprint protocol to induce muscle damage. The markers of muscle damage (soreness, range of motion, limb girth, muscle strength, creatine kinase and lactate dehydrogenase), physical performance (speed, agility and power) and balance (static and dynamic balance) were assessed at baseline and 24, 48 and 72 hours following the sprint protocol. [Results] All variables, including the markers of muscle damage, physical performance and balance showed a significant difference when assessed at the 4 time points. [Conclusion] The study demonstrated that both the physical and balance performance were affected following repeated sprint protocol in soccer players. It is recommended the balance performance of an athlete be continually assessed following exercise-induced muscle damage so as to determine the appropriate return to sport decision thereby, minimizing the risk of further injury.

Co-Existence of hypertension worsens post-exercise cardiac autonomic recovery in type 2 diabetes

Background Cardiac autonomic neuropathy (CAN) is a commonly overlooked complication of Type 2 Diabetes Mellitus (T2DM) characterized by imbalance between sympathetic and parasympathetic supply to the heart. The susceptibility of heart to dysrhythmias and fatal events increases during and after exercise due to a shift in autonomic regulation. Diabetes and hypertension (HTN) frequently occur concurrently and both conditions lead to impaired cardiac autonomic control. However, their impact together on post-exercise autonomic recovery remains to be explored. Objective The objective of the study was to investigate the effect of co-existence of HTN on cardiac autonomic recovery (assessed by heart rate recovery and heart rate variability) in patients with T2DM. Methods Forty eight type 2 diabetic patients (24 normotensive, 24 hypertensive), 24 non-diabetic patients with essential HTN, and 27 healthy controls, were recruited into the study and assessed for heart rate recovery (HRR) following a graded maximal test. Also, heart rate variability (HRV) was recorded before and following the bout of maximal exercise. Results Heart rate recovery at 1 (HRR1min) and 2 (HRR2min) minute(s) showed significant effects for DM (p < 0.001) and HTN (p < 0.001), while DM × HTN interaction was found to be non-significant. Resting HRV showed a significant decline in time-domain variables for the DM group (p < 0.01). Recovery of HRV showed a significant effect of time (p < 0.05) for all indices, the group effect was found significant only for time-domain measures (p < 0.05). Conclusion Both HRR and HRV recovery were impaired in DM and HTN. Moreover, the co-existence of HTN had a synergistic effect, causing further worsening of autonomic recovery in T2DM.

Reliability of Electromyographic Assessment of Biceps Brachii and Triceps Brachii in Cricketers

Objective The purpose of this study is to determine the intraexaminer and interexaminer reliability of electromyographic assessment of biceps brachii (BB) and triceps brachii (TB) muscles in cricketers. Methods Sixteen healthy male cricketers (ages 14‐35 years) recruited from Jamia Millia Islamia, New Delhi, India were tested on 2 occasions that were held 1 week apart. On the first occasion, only examiner 1 performed the testing; on the second occasion, examiner 1, examiner 2, and examiner 3 all performed testing. While testing for surface electromyography (sEMG) activity of BB and TB muscles, participants were asked to produce maximal voluntary isometric contraction (MVIC), which was to be held for 5 seconds against the resistance provided by an examiner. Participants performed 3 MVICs per muscle per examiner, with a rest interval of 3 minutes between consecutive contractions. Intraclass correlation coefficient, standard error of measurement, and minimum detectable change were calculated to determine the reliability of repeated sEMG measurements. Results Nonsignificant differences were observed for the 2 trials completed by examiner 1 (paired t test) and testing done by all 3 examiners (repeated measures analysis of variance) at P < .05 for both BB and TB. Intraclass correlation coefficient values ranged from .84 to .86 for BB and .89 to .98 for TB. Standard error of measurement (minimum detectable change) was .052 (.144) mV and .041 (.114) mV for BB intraexaminer and interexaminer reliability testing, respectively, and .018 (.051) mV and .043 (.119) mV for TB intraexaminer and interexaminer reliability testing. Ninety‐five percent of the mean differences between almost all of the repeated measurements were found to lie within the agreement intervals estimated by Bland‐Altman plots. Conclusion This preliminary study suggests that sEMG is a reliable tool with excellent intraexaminer and interexaminer reliability for assessing the activity of BB and TB muscles in male cricketers. These findings suggest that sEMG can be used to assess MVIC activity of these muscles in clinical settings, as well as in research area.

Heart Rate Variability following Combined Aerobic and Resistance Training in Sedentary Hypertensive Women: A Randomised Control Trial

Objective To investigate the effect of combined aerobic and resistance training (CART) on heart rate variability in sedentary, hypertensive women. Participants A total of twenty-eight hypertensive (Stage 1 and 2) sedentary women (Age 40.54 ± 4.2 yrs; Height 155.14 ± 5.4 cm; Weight 70.96 ± 10.2 kg; BMI 29.6 ± 4.4; Duration of HTN: 6.43 ± 2.5 yrs) were recruited for the study. Methods Participants were randomly assigned to either the CART group that performed combined aerobic and resistance exercise of moderate intensity [aerobic exercise 50–80% of HRmax (maximum heart rate) and resistance exercises at 50–80% of 1 Repetition Maximum (RM)], 5 times/week for 4 weeks, or to the control group that followed conventional treatment without any supervised exercise intervention. Main outcome measures Resting blood pressure was measured and standard heart rate variability (HRV) indices were calculated using time domain (SDNN, pNN50, RMSSD) and frequency domain (LFnu, HFnu, LF/HF and TP) analysis. Results CART group demonstrated an increase in HFnu, TP, SDNN, and RMSSD, (p < 0.05) along with a significant decrease in LFnu, LF/HF ratio, systolic blood pressure, and diastolic blood pressure (p < 0.05). Conclusion CART showed significant improvement in HRV parameters indicating vagal dominance in middle-aged hypertensive women. Therefore, exercise training in combined form (aerobic and resistance) may be incorporated in the management programs of the patients suffering from hypertension in order to augment improvement in their cardiac autonomic control.

Postactivation Potentiation Following Acute Bouts of Plyometric versus Heavy-Resistance Exercise in Collegiate Soccer Players

Postactivation potentiation is referred to as an acute and temporary enhancement of muscle performance resulting from previous muscle contraction. The purpose of this study was to compare the acute effect of plyometric exercise (PLY) and heavy-resistance exercise (RES) on the blood lactate level (BLa) and physical performance. Fourteen male collegiate soccer players were randomized to perform either RES or PLY first and then crossed over to perform the opposite intervention. PLY consisted of 40 jumps, whereas RES comprised ten single repetitions at 90% of one repetition maximum. BLa and physical performance (countermovement jump height and 20-m sprint) were measured before and at 1 and 10 min following the exercise. No significant difference was observed in the BLa for both exercises (PLY and RES). Relative to baseline, countermovement jump (CMJ) height was significantly better for the PLY group after 1 min (P = 0.004) and after 10 min (P = 0.001) compared to that of the RES group. The 20-m sprint time was significantly better for PLY at 10 min (P = 0.003) compared to that of RES. The present study concluded that, compared to RES, PLY causes greater potentiation, which leads to improved physical performance. This trial is registered with NCT03150277.

Effect of recovery modalities on blood lactate clearance

Recovery is an important tool for achieving an appropriate balance between training and competition stresses in maximizing the performance of athletes. Recovery modalities are being widely used as integral parts of the training programs of athletes to help in attaining this balance. This review examines the available evidence on efficacy of various modalities in enhancing recovery in athletic population with regard to their ability to improve the rate of blood lactate removal following high-intensity exercise. Modalities reviewed include massage therapy, contrast water therapy, active recovery, whole-body vibration therapy, pneumatic compression therapy, compression garments, and neuromuscular electrostimulation therapy.

Complex Training: An Update

The term ‘complex training’ refers to a training mode which combines one set of strength training with a comparable set of plyometric exercises in same training session and is believed to enhance the quality of the plyometric training stimulus. This idea of combining biomechanically similar exercises is proposed to be a favourable strategy for improving rate of force development and dynamic power by better neuromuscular control. High-intensity resistance training creates an optimal training state for the subsequent plyometric bout by means of neuromuscular, hormonal, metabolic, myogenic, and psychomotor factors that allow it to serve as a strategy for continued neural adaptations. This review aims to present the current body of knowledge regarding the effects of complex training, discussing in brief, its mechanism, the various training variables that might act to confound its efficacy and finally, its comparison with other popular modes of training. In conclusion, complex training appears to be a safe and effective mode yielding gains of both strength and power training in the same session, however, further research is warranted to better understand the operating physiological mechanisms and to derive more concrete results regarding the most optimal training variables.

Transcultural adaptation and validation of Hindi version of Quebec Back Pain Disability Scale

Abstract Purpose: To transculturally adapt the Quebec Back Pain Disability Scale for Hindi-speaking population and examine its psychometric properties in patients with low back pain. Materials and methods: The Quebec Back Pain Disability Scale was translated and cross-culturally adapted into Hindi following international guidelines. Hindi version of the scale was completed by 120 patients with low back pain and 60 healthy controls. Patients with low back pain were also administered the Hindi-Roland Morris Disability Questionnaire and Visual Analog Scale. Psychometric evaluation included test–retest reliability, convergent and discriminative validity. Exploratory factor analysis was carried out to determine the factor structure. Results: The factorial analysis revealed a four-factor solution (bending/carrying, ambulation/reach, prolonged postures and rest). Convergent validity was confirmed by high correlation of Hindi Quebec Back Pain Disability Scale to the Hindi version of Roland Morris Disability Questionnaire (r = 0.77 and p < 0.001) as well as Visual Analog Scale (r = 0.682 and p < 0.001) scores. Discriminative validity was established by significantly different scores for patients with low back pain and the healthy controls (35.36 ± 18.6 vs. 9.13 ± 6.08 and p < 0.001). The translated version of the scale showed remarkable internal consistency (Cronbach α = 0.98) and the intraclass correlation coefficient of test–retest reliability was excellent (ICC2,1=0.96). MDC95 and SEM scores obtained were 10.28 and 3.71, respectively. Conclusion: The Hindi version of Quebec Back Pain Disability Scale has good test–retest reliability, discriminative and convergent validity and is appropriate for clinical and research use in Hindi-speaking low back pain patients. Implications for rehabilitation Linguistically and culturally adapted questionnaires help researchers make adequate inferences about instruments measuring health and quality of life. The translated version would serve as a valid research tool allowing comparability of data across cultures thus, providing opportunities for large multicenter, multicountry trials. A Hindi Quebec Back Pain Disability Scale version will help to improve the quality and efficacy of assessment of low back pain by developing in patients, a better understanding of the items which can be easily correlated with the activities of daily living.

Effects of concurrent training on physical health and performance

The primary objective of this narrative review was to evaluate the current literature and to provide further insight into the role of concurrent training on various components of physical health or performance. Literature was obtained by electronic searches of databases using specific keywords. Combined effect of training sessions proved to be as beneficial as drug interactions. Results from cross-sectional, longitudinal, and intervention studies are reviewed and discussed with main focus on physical parameters, such as body composition, physiological parameters, molecular adaptation, athlete’s perspective, order of execution, interference phenomena and recovery. In conclusion, concurrent resistance and endurance training is an effective method for enhancing overall fitness as well as improving quality of life.

Reliability and Validity of EN-TreeM Dynamometer for Measurement of Shoulder Rotator Strength in Volleyball Players

INTRODUCTION Volleyball involves repeated forceful arm actions that produce a high incidence of shoulder injury. Shoulder rotator strength ratio is an important predictor of the likelihood of shoulder injury, especially, secondary shoulder impingement and instability. Therefore, assessment of muscle strength of external and internal rotators of shoulder is imperative to establish the profiles of shoulder rotator performance, strength ratios, and shoulder mobility of volleyball players. AIM To establish reliability and validity of EN-TreeM dynamometer for the measurement of shoulder rotators strength in volleyball players. MATERIALS AND METHODS Thirty male volleyball players aged 18-24 years, mean height 1.7m, weight 69.8 Kg and BMI 23.1 participated in the study. They performed 1RM (one repetition maximum) estimation protocols using EN-TreeM dynamometer and free weights for shoulder rotators, to investigate its concurrent validity. A retest using the same protocol was performed 48 hours later to assess test-retest reliability of the EN-TreeM dynamometer. RESULTS The results yielded excellent test-retest reliability (ICC0.96) and internal consistency (Cronbachs alpha0.98) for both internal and external rotators. The concurrent validity was established using Pearson correlation coefficient (internal rotator r=0.45, p=0.01;External rotator r=0.38, p=0.03). CONCLUSION The findings establish the reliability and concurrent validity of EN-TreeM dynamometer for the quantification of shoulder rotators strength. Based on these findings in volleyball players, EN-TreeM dynamometer can be used with confidence as an instrument for assessing muscle performance (strength). Additionally, it may also be used for monitoring changes due to rehabilitation interventions in shoulder injuries.