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Objective: To determine whether acupotomy ameliorates immobilization-induced muscle contracture and fibrosis via Wnt/β-catenin signaling pathway. Methods: Thirty Wistar rats were randomly divided into 5 groups (n=6) by a random number table, including control, immobilization, passive stretching, acupotomy, and acupotomy 3 weeks (3-w) groups. The rat model of gastrocnemius contracture was established by immobilizing the right hind limb in plantar flexion for 4 weeks. Rats in the passive stretching group received passive stretching at gastrocnemius, a daily series of 10 repetitions for 30 s each at 30-s intervals for 10 consecutive days. Rats in the acupotomy and acupotomy 3-w groups received acupotomy once and combined with passive stretching at gastrocnemius a daily series of 10 repetitions for 30 s each at 30-s intervals for 10 consecutive days. Additionally, rats in the acupotomy 3-w group were allowed to walk freely for 3 weeks after 10-day therapy. After treatment, range of motion (ROM), gait analysis [i.e., paw area, stance/swing and maximum ratio of paw area to paw area duration (Max dA/dT)], gastrocnemius wet weight and the ratio of muscle wet weight to body weight (MWW/BW) were tested. Gastrocnemius morphometric and muscle fiber cross-sectional area (CSA) were assessed by hematoxylin-eosin staining. Fibrosis-related mRNA expressions (i.e., Wnt 1, β-catenin, axin-2, α-smooth muscle actin, fibronectin, and types I and III collagen) were measured using real-time quantitative polymerase chain reactions. Wnt 1, β-catenin and fibronectin concentrations were measured by enzyme-linked immunosorbent assay. Types I and III collagen in the perimysium and endomysium were analyzed using immunofluorescence. Results: Compared with the control group, ROM, gait function, muscle weight, MWW/BW and CSA were significantly decreased in the immobilization group (all P<0.01), while protein levels of types I and III collagen, Wnt 1, β-catenin, fibronectin and mRNA levels of fibrosis-related genes were obviously increased (all P<0.01). Treatment with passive stretching or acupotomy restored ROM and gait function and increased muscle wet weight, MWW/BW and CSA (all P<0.05), while protein expression levels of Wnt 1, β-catenin, fibronectin, types I and III collagen and mRNA levels of fibrosis-related genes were remarkably declined compared with the immobilization group (all P<0.05). Compared with passive stretching group, ROM, gait function, MWW was remarkably restored (all P<0.05), and mRNA levels of fibrosis-related genes as well as protein expression levels of Wnt 1, β-catenin, fibronectin, types I and III collagen in the acupotomy group were obviously decreased (all P<0.05). Compared with the acupotomy group, ROM, paw area, Max dA/dT, and MWW were restored (all P<0.05), and mRNA levels of fibrosis-related genes along with protein levels of Wnt 1, β-catenin, fibronectin, types I and III collagen in the acupotomy 3-w group were decreased (P<0.05). Conclusion: Improvements in motor function, muscle contractures, and muscle fibrosis induced by acupotomy correlates with the inhibition of Wnt/β-catenin signaling pathway. [ABSTRACT FROM AUTHOR]

Purpose: Reactive oxygen and nitrogen species are required for exercise-induced molecular adaptations; however, excessive exercise may cause cellular oxidative distress. We postulate that astaxanthin (ASX) can neutralize oxidative distress and stimulate mitochondrial biogenesis in high-intensity exercise-trained mice. Methods: Six-week-old mice (n = 8/group) were treated with ASX (10 mg/kg BW) or placebo. Training groups participated in 30 min/day high-intensity interval training (HIIT) for 6 weeks. Gastrocnemius muscle was collected and assayed following the exercise training period. Results: Compared to the HIIT control mice, the ASX-treated HIIT mice reduced malonaldehyde levels and upregulated the expression of Nrf2 and FOXO3a. Meanwhile, the genes NQO1 and GCLC, modulated by Nrf2, and SOD2, regulated by FOXO3a, and GPx4, were transcriptionally upregulated in the ASX-treated HIIT group. Meanwhile, the expression of energy sensors, AMPK, SIRT1, and SIRT3, increased in the ASX-treated HIIT group compared to the HIIT control group. Additionally, PGC-1α, regulated by AMPK and SIRT1, was upregulated in the ASX-treated HIIT group. Further, the increased PGC-1α stimulated the transcript of NRF1 and Tfam and mitochondrial proteins IDH2 and ATP50. Finally, the ASX-treated HIIT mice had upregulations in the transcript level of mitochondrial fusion factors, including Mfn1, Mfn2, and OPA1. However, the protein level of AMPK, SIRT1, and FOXO3a, and the transcript level of Nrf2, NQO1, PGC-1α, NRF1, Mfn1, Mfn2, and OPA1 decreased in the HIIT control group compared to the sedentary control group. Conclusion: Supplementation with ASX can reduce oxidative stress and promote antioxidant capacity and mitochondrial biogenesis during strenuous HIIT exercise in mice. [ABSTRACT FROM AUTHOR]

Background: Dual task influences postural control. A cognitive task seems to reduce muscle excitation during a postural balance, especially in older adults (OA). Aim: The aim of this study is to evaluate the effect of three cognitive tasks on muscle excitation and static postural control in OA and young adults (YA) in an upright posture maintenance task. Methods: 31 YA and 30 OA were evaluated while performing a modified Romberg Test in five different conditions over a force plate: open eyes, closed eyes, spatial-memory brooks' test, counting backwards aloud test and mental arithmetic task. The surface electromyographic signals of Tibialis anterior (TA), Lateral Gastrocnemius (GL), Peroneus Longus (PL), and Erector Spinae (ES) was acquired with an 8-channel surface electromyographic system. The following variables were computed for both the electromyographic analysis and the posturographic assessment: Root mean square (RMS), centre of pressure (CoP) excursion (Path) and velocity, sway area, RMS of the CoP Path and 50%, 95% of the power frequency. Mixed ANOVA was used to detect differences with group membership as factor between and type of task as within. The analysis was performed on the differences between each condition from OE. Results: An interaction effect was found for Log (logarithmic) Sway Area. A main effect for task emerged on all posturographic variables except Log 95% frequencies and for Log PL and ES RMS. A main effect for group was never detected. Discussion and conclusion: This study indicates a facilitating effect of mental secondary task on posturographic variables. Non-silent secondary task causes increase in ES and TA muscle activation and a worsening in static postural control performance. [ABSTRACT FROM AUTHOR]

Purpose: In our previous study, the maternal high-fat/low-fiber (HF-LF) diet was suggested to induce metabolic disorders and placental dysfunction of the dam, but the effects of this diet on glucose metabolism of neonatal offspring remain largely unknown. Here, a neonatal pig model was used to evaluate the effects of maternal HF-LF diet during pregnancy on glucose tolerance, transition of skeletal muscle fiber types, and mitochondrial function in offspring. Methods: A total of 66 pregnant gilts (Guangdong Small-ear Spotted pig) at day 60 of gestation were randomly divided into two groups: control group (CON group; 2.86% crude fat, 9.37% crude fiber), and high-fat/low-fiber diet group (HF-LF group; 5.99% crude fat, 4.13% crude fiber). Results: The maternal HF-LF diet was shown to impair the glucose tolerance of neonatal offspring, downregulate the protein level of slow-twitch fiber myosin heavy chain I (MyHC I), and upregulate the protein levels of fast-twitch fiber myosin heavy chain IIb (MyHC IIb) and IIx (MyHC IIx) in soleus muscle. Additionally, compared with the CON group, the HF-LF offspring showed inhibition of insulin signaling pathway and decrease in mitochondrial function in liver and soleus muscle. Conclusion: Maternal HF-LF diet during pregnancy impairs glucose tolerance, induces the formation of glycolytic muscle fibers, and decreases the hepatic and muscular mitochondrial function in neonatal piglets. [ABSTRACT FROM AUTHOR]

Background & aims: The Global Leadership Initiative on Malnutrition (GLIM) is new criteria for diagnosing malnutrition that need validation adjusted to race. Our aim is to determine the optimal reference values of calf circumference (CC), investigate the prevalence of GLIM-defined malnutrition based on different screening tools in inpatients over 70 years old in China and assess its relationship with clinical outcomes. Methods: We designed two continuity studies by analyzing a prospective multicenter database. First, we estimated and validated the CC cut-off values by receiver operating characteristic analyses against in-hospital mortality. Then the patients who were at risk by NRS 2002, MNA-SF and MUST were assessed by the GLIM criteria using the new CC values. Some clinical parameters and outcome data were evaluated. Results: The optimal cut-off values of CC were 29.6 cm for male patients and 27.5 cm for female patients. The prevalence of GLIM-defined malnutrition was 27.5% by using NRS2002, 32.6% by using MNA-SF and 25.4% by using MUST. Patients with GLIM-defined malnutrition showed significantly worse values in BMI, total protein, albumin, neutrophil/lymphocyte ratio, CC, rate of complication, in-hospital mortality, length of stay, and total hospital cost than normal patients. Multivariate logistic regression showed the odds ratio of in-hospital mortality was significantly associated with GLIM defined malnutrition by using MNA-SF [OR = 1.231, 95%CI (1.022, 1.484), P = 0.029]. Conclusions: The Chinese reference values of CC for inpatients over 70 years old were validated by in-hospital mortality, which could be implemented in GLIM criteria. And this population possessed a high prevalence of nutrition risk and malnutrition. GLIM criteria with MNA-SF seems to be the first choice to diagnose malnutrition. [ABSTRACT FROM AUTHOR]

Background: Patients who have had an Achilles tendon (AT) rupture repaired are potentially at higher risk for re-rupture than those without previous rupture. Little attention has been given to the neuromechanical modulation of muscle-tendon interaction and muscle activation profiles during human dynamic movements after AT rupture repair. Objective: The purpose of this study was to examine muscle-tendon behavior and muscle activation during bilateral hopping. Methods: We enrolled nine subjects who had undergone surgical repair of unilateral AT rupture within the past 1-2 years. Subjects performed bilateral hopping while we took ultrasound, kinematic, and electromyogram recordings and measurements. AT behaviors were also recorded. We then compared responses between values obtained from the ruptured AT leg (LEG) and non-ruptured AT leg (LEG). Results: During hopping, the AT stretching amplitudes were greater in the LEG than in the LEG, although the peak AT force and stiffness were smaller in the LEG than in the LEG. The AT negative mechanical work did not show any significant differences between both legs. However, positive works were significantly lower in the LEG than in the LEG. Electromyogram patterns in both soleus and tibialis anterior muscles clearly differed after ground contact for the LEG and the LEG. Conclusions: These results suggest that the repaired ruptured AT can be compliant and have insufficient Young's modulus, which can influence mechanical responses in muscle activities. The modulation of agonist-antagonist muscle activities corresponding to the different levels of stiffness between the LEG and the LEG may not be fully functioning during the pre-activation phase. [ABSTRACT FROM AUTHOR]

An editorial is presented that discusses about the screening for sarcopenia, which derived from the Greek term meaning poverty of flesh and redefined as the loss of muscle function or strength in the presence of low lean body mass. It mentions two other forms of sarcopenia as secondary sarcopenia, which occurs in persons with chronic diseases, example diabetes mellitus, and second is sarcopenic obesity.

Ageing reduces fatigue during submaximal intermittent contractions, but the influence of intensity on this ageing effect in males and females is not clear. Younger males ( n = 8; 23 ± 2 years), younger females ( n = 8; 22 ± 1 years), older males ( n = 8; 67 ± 5 years) and older females ( n = 10; 64 ± 7 years) completed intermittent calf contractions at four submaximal intensities (30-70 %MVC) for up to 20 min. MVC was assessed during exercise at 30-60 s intervals and its linear rate of decline represented fatigue. Individual relationships between intensity and fatigue (%MVC min) were fitted to a biphasic function consisting of a linear and nonlinear component. There was no age × sex × intensity interaction for fatigue (3-way ANOVA, P = 0.46). However, there were significant interactive effects of age and sex on endurance at 70 %MVC, fatigue at 70 %MVC and the linear component of the intensity-fatigue relationship. Endurance was lower and fatigue and its linear component were greater ( P < 0.05) in younger males compared with other groups, but not different between younger and older females. This suggests that there is an intensity-dependent effect of human ageing on fatigue during submaximal exercise that is specific to males. [ABSTRACT FROM AUTHOR]

Purpose: There is a large number of publications evaluating neuromuscular risk factors for anterior cruciate ligament (ACL) injury in athletes. However, most of them have involved the female athlete and, in addition, the gastrocnemius muscles have been less investigated by far compared with the quadriceps and hamstring. The purpose of this study was to investigate the role of the gastrocnemius muscles as neuromuscular risk factors for ACL injury in male soccer players, through tensiomyography (TMG). Methods: All competitive male soccer players with confirmed ACL tear included in this study underwent resting TMG assessment of gastrocnemius medialis (GM) and gastrocnemius lateralis muscles of the uninjured side. The same values were obtained from a sex-, and sports level-matched control group in both sides. The maximal displacement (D m), delay time (T d), contraction time (T c), sustained time (T s), and half-relaxation time (T r) were obtained for both muscles. TMG values of the uninjured side in ACL-injured group were compared with the mean values between both sides in the control subjects. Results: There were no significant between-group differences in demographic characteristics. Most TMG parameters of the gastrocnemius muscles were not significantly different between the two groups. Only the GM-T r (p = 0.02) and GM-D m (p = 0.006) were significantly higher in the ACL-injured group compared with control group. Conclusions: Neuromuscular characteristics in terms of mechanical and contractile properties of the gastrocnemius muscles may not be significant risk factors for ACL injury in male soccer players. [ABSTRACT FROM AUTHOR]

Purpose: The present study analyzes the effect of the replacement of dietary casein by soy protein on the mechanisms underlying dyslipidemia, liver steatosis and altered glucose and lipid metabolism in the skeletal muscle which developed in rats fed long-term a sucrose-rich diet (SRD). Methods: Wistar rats were fed a SRD for 4 months. From months 4 to 8, half the animals continued with the SRD, and the other half were fed a SRD in which the source of protein casein was replaced by soy. The control group received a diet with cornstarch as source of carbohydrate. Results: Compared to SRD-fed animals, the rats fed soy showed: A-in the liver: reduction of triglyceride and cholesterol storage and decreased steatosis; normalization of mature forms of the protein mass levels of SREBP-1 and the activities of lipogenic enzymes, while the protein mass level of PPAR-α and fatty acid oxidase activity increased. B-in the gastrocnemius muscle: normalization of the enhanced lipid storage and the altered glucose oxidation, improving glucose phosphorylation; decreasing protein mass level of nPKCθ in the membrane fraction; reversion of the impaired insulin-stimulated glucose transporter Glut-4, and glucose-6-phosphate and glycogen concentrations. Besides, dyslipidemia and glucose homeostasis returned to control values. Conclusions: This study provides new information concerning some key mechanisms related to the effect of dietary soy on hepatic lipid metabolism and insulin action in the skeletal muscle in the presence of pre-existing dyslipidemia and insulin resistance induced by a SRD. [ABSTRACT FROM AUTHOR]

Purpose: This study examined whether changes in pH throughout the physiologic range would have a differential effect on central and peripheral factors associated with fatigue and force production during submaximal lower limb isometric exercise to task failure. Methods: Eight males completed three experimental trials [0.2 g kg ammonia chloride (ACD); 0.3 g kg calcium carbonate (PLA); or 0.3 g kg sodium bicarbonate (ALK)], each consisting of submaximal calf contractions at 55 % of maximal voluntary contraction (MVC) to task failure. Every minute of the task subjects performed an MVC, coupled with stimulation of the tibial nerve during and immediately post MVC. Results: Time to task failure was not different between trials (ACD 531 ± 166 s, PLA 592 ± 163 s, ALK 596 ± 150 s; p = 0.31). MVC force in all trials declined 29 % from the start of exercise to the fifth minute (mean decline of 371 ± 26 N; p < 0.001), however was not different between trials ( p = 0.21). Fatigue was mediated in all trials by central and peripheral factors, as declines in voluntary activation, V/M-wave in the soleus and the potentiated resting twitch amplitudes were evident throughout the task ( p < 0.05). Central fatigue appeared to be muscle specific, as reductions in central drive (V/M-wave and rate of sEMG rise) persisted in the soleus but not the medial gastrocnemius. Conclusions: These data suggest that calf fatigue associated with intermittent, isometric contractions to task failure is unaffected by alterations in pH; however, central drive reductions may be muscle specific. [ABSTRACT FROM AUTHOR]

Purpose: Calf venous compliance ( C) is commonly evaluated with venous occlusion plethysmography (VOP) during a standard cuff deflation protocol. However, the technique relies on two not previously validated assumptions concerning thigh cuff pressure ( P) transmission and the impact of net fluid filtration ( F) on C. The aim was to validate VOP in the lower limb and to develop a model to correct for F during VOP. Methods: Strain-gauge technique was used to study calf volume changes in 15 women and 10 age-matched men. A thigh cuff was inflated to 60 mmHg for 4 and 8 min with a subsequent decrease of 1 mmHg s. Intravenous pressure ( P) was measured simultaneously. C was determined with the commonly used equation [Compliance = β + 2 β × P] describing the pressure-compliance relationship. A model was developed to identify and correct for F. Results: Transmission of P to P was 100 %. The decrease in P correlated well with P reduction ( r = 0.99, P < 0.001). Overall, our model showed that C was underestimated when F was not accounted for (all P < 0.01). F was higher in women ( P < 0.01) and showed a more pronounced effect on C compared to men ( P < 0.05). The impact of F was similar during 4- and 8-min VOP. Conclusions: P is an adequate substitute for P in the lower limb. F is associated with an underestimation of C and differences in the effect of F during VOP can be accounted for with the correction model. Thus, our model seems to be a valuable tool in future studies of venous wall function. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to determine the diagnostic accuracy of the CC-SF, which was developed to use calf circumference (CC) instead of BMI in the MNA-SF, for elderly people living in the community and in nursing homes. It also aimed separately to determine the correlation of CC-SF and BMI-SF with the full MNA. Study Design and Methods: The study included 640 elderly people living in their community and 243 elderly people living in nursing homes. Accuracy was assessed by determining the sensitivity and selectivity of the nutritional assessments. The correlations between the MNA-SFs and the full MNA were analyzed. Results: The correlation between MNA-SFs and full MNAs was strong, significant and almost identical both in the community and in nursing homes (r=0.86-0.88; p<0.001). The observed agreement between the BMI-SF and the full MNA was 82.2% in the community and 77.8% in the nursing homes. There was a substantial agreement by kappa values in the comparison of community and nursing homes (the Kappa value of the BMI-SF was 0.63 in the community and 0.62 in the nursing homes, and the kappa value of the CC-SF was 0.62 in the community and 0.63 in the nursing homes). When compared to the full MNA the MNA-SFs tended to underestimate nutritional status. Both MNA-SFs had similarly high sensitivity and selectivity, both in the community and nursing homes. (when dichotomized as 'malnourished-at risk of malnutrition' versus 'well nourished' and 'malnourished' versus 'at risk of malnutrition-well nourished') (over 80%). Conclusion: In cases where BMI cannot be determined, the CC-SF is a good substitute for the BMI-SF. [ABSTRACT FROM AUTHOR]

Purpose: Few studies have assessed the time-dependent response of fatigue (i.e., loss of force) during submaximal exercise without the use of maximum contractions. There is unexplored potential in the use of the superimposed muscle twitch (SIT), evoked by transcranial magnetic stimulation (TMS) or motor nerve stimulation (MNS), to assess fatigue during voluntary submaximal contractions. For the human triceps surae muscles, there are also no data on TMS-evoked twitches. Methods: To optimise the TMS stimulus for assessment of fatigue, we first tested the effects of TMS power (40, 55, 70, 85, 100 % max) on SIT force during contractions (0-100 % MVC in 10 % increments) in six subjects. Then, we compared SIT responses (TMS and MNS) during submaximal contractions and MVCs (all at 60 s intervals) during a continuous protocol of intermittent contractions (30 % MVC) consisting of consecutive 5 min periods of baseline, fatigue (ischaemia) and recovery. Results: For TMS, SIT force increased as a diminishing function of TMS power ( P < 0.05), the relationships between SIT force and the force of voluntary contraction at all TMS powers were parabolic, and SIT force was maximised at ~20-40 % MVC. During intermittent contractions, MVC and SIT forces were stable during baseline, decreased similarly during ischaemia by 40-50 % ( P < 0.05), and recovered similarly to baseline values ( P > 0.05) before the end of the protocol. Conclusion: TMS can be used to evoke twitches during submaximal contractions of the human calf muscle and, along with MNS, used to assess fatigue during submaximal exercise. [ABSTRACT FROM AUTHOR]

To clarify the structure of the muscle hyperaemic response during submaximal exercise in the supine position, we tested the hypotheses that this response measured in human calf muscle is biphasic or triphasic (growth-only) at low-moderate or high forces, respectively. Ten subjects performed four series of 5-min bout of intermittent contractions from a resting baseline to 30, 60 and 90% of peak force, as well as from an exercise baseline to higher forces. For each exercise transition, leg blood flow (LBF: plethysmography) and leg vascular conductance (LVC) were measured between contractions and averaged across four trials. Six 'growth-only' and 'growth and decay' models were fitted to these averaged responses and significant differences between their goodness-of-fit were tested statistically. For rest-exercise transitions, triphasic or quadphasic 'growth and decay' models provided the best fit to the majority of LBF and LVC responses. The intensity-dependent growth in hyperaemia was due mainly to a significant increase in amplitude of the rapid growth phase. A fast decay in LBF and LVC occurred at all intensities (mean τ = 4-5 s, mean TD = 9-14 s). A slower decay appeared at the lowest intensity (mean τ = 18-28 s, TD ≅ 90 s) that coincided with a monoexponential decline in EMG activity (mean τ = 23, TD = 87 s). Thus, although biphasic growth is an essential feature of muscle hyperaemia, rapid and slow decay phases also exist that highlight additional mechanisms which contribute to this dynamic response during exercise. [ABSTRACT FROM AUTHOR]

Aim: To verify whether moderate physical training affects the muscle fibre composition of adult rats subjected to a low protein diet during the perinatal period. Methods: Male Wistar rats were divided into two groups according to their mother's diet during gestation and lactation: control (17% casein, C) and low-protein (8% casein, LP). On postnatal day 60, half of each group was submitted to moderate physical training (8 weeks, 5 days/week, 60 min/day, at 70% of VO, T) or not. After the physical training period, soleus and extensor digitorum longus (EDL) muscles were removed. Myofibrillar ATPase staining was used to classify muscle fibres as type I, IIa, IIb, and intermediate. Results: In the EDL muscle, LP rats showed no changes in the fibre type proportion. Both the C + T and LP + T groups showed a higher percentage of fibres of type IIa, and a lower proportion of fibres of type IIb. In the soleus muscle, LP animals showed a reduction in the proportion of fibre types I and intermediate. C + T rats showed an increase in the fibre type I and IIa. In the LP + T rats, the proportions of the fibre types remained similar to control rats. Conclusions: Moderate physical training acts as a positive environmental stimulus that reverts the effects of a perinatal low-protein diet on the proportion of fibre types in skeletal muscle. [ABSTRACT FROM AUTHOR]

Background: The venous stasis of soleal vein during surgery may be an important factor in the development of deep vein thrombosis (DVT). The stimulation of calf muscle during surgery may help in preventing DVT. The present study is conducted to evaluate the role of peroperative calf muscle electrostimulation in prevention of DVT in patients undergoing surgeries around the hip joint. Materials and Methods: The study comprised 200 patients undergoing surgeries around the hip joint. The patients having risk factors (such as previous myocardial infarction, malignancies, paraplegia or lower limb monoplegia, previous history of DVT or varicose veins, etc.) for the development of DVT were excluded. They were randomized into two groups: 100 cases were given peroperative calf muscle electrostimulation for DVT prophylaxis (Group A) and the remaining 100 patients were taken as controls without any prophylaxis (Group B). The color Doppler ultrasound was performed to exclude pre-existing DVT and on 7th day postoperative to find out the incidence of DVT in both the groups. Results: Two patients among Group A and six patients among Group B demonstrated DVT on ultrasonography, but the difference was not found to be statistically significant (P=0.279). None of the patients had any clinical evidence of DVT. Conclusion: The role of peroperative calf muscle electrostimulation for DVT prophylaxis remains controversial. The risk of developing DVT in patients undergoing surgeries around the hip joint is very less in patients analysed in our series. [ABSTRACT FROM AUTHOR]

Achilles tendinopathy (AT) is a common injury in running sports. While the exact aetiology of Achilles injury is still unclear, foot orthoses are often effectively employed in the conservative management of the condition. Foot orthoses have traditionally been provided for people with AT on the basis that they may reduce the rearfoot eversion associated with excessive foot pronation. This increased rearfoot motion is thought to produce excessive Achilles tendon loads. To date, the available literature indicates that foot orthoses have small and unsystematic effects on rearfoot kinematics. However, limitations of foot kinematic measurement currently restrict the ability to conduct truly valid investigations into kinematic responses to foot orthoses. Therefore, the roles of alternate mechanisms, for which orthoses may provide clinical success in pathology such as AT, are now being investigated. One alternative theory is that foot orthoses alter neuromotor recruitment patterns and thus lower limb loads in response to the additional sensory input provided by the device. In AT, altered neuromotor recruitment patterns of the triceps surae have been hypothesized to create differential intratendinous loads. This may lead to pathological changes within the tendon. Furthermore, it is possible that foot orthoses may aid to normalize intratendinous loads via altering neuromotor activity in the triceps surae in AT. This review examines the literature with regard to changes in neuromotor recruitment as an associated aetiological factor in AT and the role foot orthoses may play in the management of this condition. [ABSTRACT FROM AUTHOR]