Effect of Yoga or Physical Exercise on Muscle Function in Rural Indian Children: A Randomized Controlled Trial

BACKGROUND

Synergistic effects of yoga or physical exercise (PE) along with protein supplementation on children's muscle function in rural India have not been studied. Hence, we aimed to study the effect of yoga and PE along with protein supplementation on muscle function in healthy 6- to 11-year-old rural Indian children post 6 months of intervention.

METHODS

A randomized controlled trial on 232 children, recruited into 3 groups, each receiving 1 protein-rich ladoo (148 kcal, 7 g protein/40 g ladoo-an Indian sweet snack) daily and performing (1) yoga (n = 78) for 30 minutes 5 times per week, (2) PE (n = 76) for 30 minutes 5 times per week, or (3) control group (n = 78) no additional exercise. Maximum power, maximum voluntary force (Fmax), and grip strength (GS) were measured. Data were analyzed using paired t tests and a 2-way mixed analysis of variance with post hoc Bonferroni adjustment.

RESULTS

GS, maximum power, and Fmax within yoga group increased significantly (P < .05) from baseline to endline. GS and Fmax increased significantly within PE group postintervention (P < .001). In controls, GS increased (P < .05) at endline. No significant effect of the intervention was observed on the change in maximum power (P > .05) postintervention. The 2 exercise groups showed significant increase in Fmax compared with the control group (P < .05). Similarly, increase in GS was significantly higher in both the exercise groups compared with the control group (P < .05). No significant difference was observed in change in muscle function between the 2 exercise groups (P > .05).

CONCLUSIONS

Structured physical activity along with protein supplementation resulted in improved muscle function in children. Yoga and PE showed a comparable impact on muscle force.

Jumping Mechanography: Reference Centiles in Childhood and Introduction of the Nerve-Muscle Index to Quantify Motor Efficiency

Jumping mechanography provides robust motor function indicators among children. The study aim was to develop centiles for the single 2-leg jump (S2LJ) in German children and adolescents and to identify differences in children with obesity. Data were collected in 2004-2021 through the German DOrtmund Nutritional and Anthropometric Longitudinally Designed (DONALD) study. All participants (6-18 years, mean age 11.4) performed annually an S2LJ aiming for maximum height on a Ground Reaction Force Platform. LMS (lambda-mu-sigma), including resampling, was used to develop centiles for velocity (vmax), jump height (hmax), relative force (Fmax/BW), relative power (Pmax/mass), impulse asymmetry and a new parameter to describe jump efficiency, the Nerve-Muscle Index (NMI), defined as vmax/(Fmax/BW). Data from 882 children and adolescents were analyzed (3062 measurements, median 3 per individual). In females, Fmax/BW values were higher in younger age but remained constant in adolescence. vmax, hmax and Pmax/mass increased in childhood, reaching a plateau in adolescence. In males, vmax, hmax and Pmax/mass showed a constant increase and the Fmax/BW remained lower. Children with obesity showed lower Fmax/BW, hmax, vmax and the NMI, hence, lower velocity per relative force unit and less efficient jump. The centiles should be used to monitor motor development in childhood. The NMI is a surrogate for motor efficiency.

Increase of jump performance during GH treatment in short children born SGA

Background

Short children born small for gestational age (SGA) often have low muscle mass. Studies on maximal isometric grip-force (MIGF) observed lower muscle strength in these children. In contrast to MIGF, jumping is an everyday muscle activity for children. Our hypothesis was that GH treatment would cause an increase in jumping strength. So, we aimed to study jumping by mechanography in short SGA children before and during GH treatment.

Methods

Monocentric prospective longitudinal study in a tertiary pediatric endocrinology center. We studied 50 prepubertal short children (23 females) born SGA (mean age 7.2 y, height -3.24 SDS) during GH treatment (mean dose 45 µg/kg/d). Main outcome measures were Peak jump force (PJF) and peak jump power (PJP) measured by Leonardo^® ground reaction force plate at baseline and after 12 months of GH treatment. Mechanography data were compared to sex, age and height related references (SD-Score). Fitness was estimated as PJP/kg body weight by use of the Esslinger-Fitness-Index (EFI).

Results

At start of GH treatment PJP/body weight was low at -1.52 SDS and increased significantly to -0.95 SDS during 12 months of treatment (p<0.001). PJF was low-normal compared to height dependent references and remained unchanged. PJP was normal compared to height dependent references and increased only slightly from -0.34 to -0.19 SDS_HT.

Conclusions

Jumping performance (EFI) measured by mechanography increased during one year of GH treatment in short children born SGA.

Normative-referenced percentile values for physical fitness among Canadians

BACKGROUND

This study developed age- and sex-specific normative-referenced percentile values for five physical fitness tests across a wide age range of Canadians, using a nationally representative sample.

DATA AND METHODS

The data are from 5,188 Canadians (50.1% female) and were collected as part of cycle 5 of the Canadian Health Measures Survey (2016 to 2017).

RESULTS

Males had slightly better cardiorespiratory fitness and substantially better grip strength, jumping height and jumping power scores than females, whereas females had better sit-and-reach flexibility. Among females, there were pronounced increases in jumping height (P50: 25%) and jumping power (P50: 58%) between ages 8 and 13, and in grip strength (P50: 193%) between ages 6 and 19. Performance gradually declined with age, beginning in adolescence for jumping ability and at approximately age 35 for grip strength. Among males, there were pronounced increases in jumping height (P50: 69%) and jumping power (P50: 233%) between ages 8 and 20, and in grip strength (P50: 365%) between ages 6 and 20. Performance gradually declined with age, beginning immediately after adolescence for jumping ability and at approximately age 30 for grip strength. Sit-and-reach flexibility remained relatively stable with age in both sexes. Cardiorespiratory fitness scores in both sexes declined steadily with age beginning (generally) at age 8, with a larger decline evident in females until age 18.

DISCUSSION

These normative-referenced values for physical fitness could be useful for screening in public health and clinical practice.

Experience with jumping mechanography in children with cerebral palsy

OBJECTIVES

Jumping mechanography provides robust motor function indicators among healthy children. The aim of the study was to assess the reproducibility and validity of jumping mechanography conducted as single two-legged jump (S2LJ) in children with cerebral palsy (CP).

METHODS

215 S2LJ investigations from a sample of 75 children with CP were eligible for evaluation. For the estimation of the reproducibility, only the baseline set of data per patient were used. Gross motor function was evaluated by the Gross Motor Function Measure (GMFM-66). In 135 S2LJ investigations, GMFM-66 was assessed within a week in the same child. This data was used for validity assessment.

RESULTS

Coefficients of variation for the main outcome parameters ranged between 6.15-9.71%, except for jump height (CV%=27.3%). The intraclass correlation coefficients for peak velocity (V_max) and peak power relative to body weight (P_max/mass) was 0.927 and 0.931. V_max and P_max/mass were also the test parameters with the strongest correlation to the GMFM-66 score (⟩0.7).

CONCLUSIONS

S2LJ assessed in the present study provided reproducible outcome measures particularly for Vmax and Pmax/mass in children with CP. Further, V_max and P_max/mass showed the strongest correlation with the GMFM-66 score and seem to be the most relevant evaluation criteria.

Reference data for jumping mechanography in Canadian children, adolescents and young adults

OBJECTIVES

To provide age- and sex-specific reference data for mechanography-derived parameters of muscle function in Canadian children and youth using the single two-legged jump (S2LJ) with hands-on-waist.

METHODS

Our sample included 2017 observations from 715 participants (9-21 years; 338 girls). Participants performed three S2LJ with hands-on-waist on a force platform (Leonardo Mechanograph, Novotec). Outcomes were maximum peak power (P_max), P_max/mass, peak force/body weight (F_max/BW), force efficiency, maximum jump height (H_max), and velocity (V_max). We used the LMS method to construct age- and sex-specific percentile curves and mixed effects models to examine sex and ethnic differences.

RESULTS

With the exception of Efficiency, mechanography outcomes were greater in girls (4-40%, p<0.05) than boys at age 9. Boys' advantage in mechanography parameters emerged in adolescence (age 11-13 years; 3-65%, p<0.05) and persisted into young adulthood, except for F_max/BW which was not greater in boys until age 17 (4-10%, p<0.05). Mechanography outcomes were 3-9% (p<0.05) greater in Asian compared with white participants.

CONCLUSIONS

We provide the first reference data for the S2LJ using the hands-on-waist protocol in children, youth and young adults. These data support previous findings using freely moving arms and can be used when evaluating muscle function in pediatric studies.

Effect of age and sex on jumping mechanography and other measures of muscle mass and function

OBJECTIVES

Sarcopenia increases falls and fracture risk. Sarcopenia clinical trials require robust quantitative tools to evaluate muscle function; jumping mechanography (JM) is likely one such tool. However, US data comparing JM with traditional tests across the lifespan is limited. This study evaluated the effect of age and sex on JM compared with traditional function tests and lean mass.

METHODS

US adults (213 women/119 men; mean age 65.4 years, range 27-96) performed functional tests including JM, Short Physical Performance Battery (SPPB) and grip strength (GS). Appendicular lean mass (ALM) was measured using DXA.

RESULTS

Men had higher relative jump power [mean (SD) 28.5 (10.52) vs. 21.9 (7.11) W/kg], GS [35.5 (9.84) vs. 22.7 (6.98) kg] and ALM/ht(2) [8.25 (1.35) vs. 6.99 (1.38) kg/m2] (all p<0.0001); no difference was observed for SPPB components. JM parameters were more strongly correlated with age than traditional tests (R2=0.38-0.61 vs. R2=0.01-0.28) and weakly with GS and chair rise time (R2=0.30-0.36).

CONCLUSION

JM parameters are correlated with GS and chair rise time and demonstrate stronger correlations with age. JM shows promise as a valuable tool to evaluate and monitor interventions for sarcopenia as it could potentially detect change in muscle function more precisely than existing tools.