Forearm electromyographic activity during the deadlift exercise is affected by grip type and sex

Effects of isometric training and R.I.C.E. treatment on the arm muscle performance of swimmers with elbow pain

The effects of IT and R.I.C.E. treatment on arm muscle performance in overhead athletes with elbow pain (EP) have been partially validated. However, there is a lack of research evidence regarding the efficacy of these two methods on arm muscle performance among swimmers with EP. The aim of this study was to investigate the trends and differences in the effects of IT and R.I.C.E. treatment on arm muscle performance among swimmers with EP. The main outcomes were the time effects and group effects of interventions on muscle voluntary contraction (MVC). Sixty elite freestyle swimmers from Tianjin, China, voluntarily participated in the study and completed a 10-week intervention program. Swimmers with EP in the IT group showed a positive trend in MVC, with an approximately 2% increase, whereas the MVC of subjects in the R.I.C.E. treatment group and control group decreased by approximately 4% and 5%, respectively. In comparison, the effects of the IT intervention on the MVC of the triceps and brachioradialis muscles in swimmers with EP were significant (p = 0.042 < 0.05, p = 0.027 < 0.05). The mean MVC value of the IT group (0.60) was greater than that of the other two groups (0.51, 0.50). IT has a beneficial impact on the MVC performance of the triceps and brachioradialis muscles in swimmers with EP. It is recommended that professionals consider incorporating IT into regular training routines to mitigate the risk of EP issues. Future research should examine the effectiveness of both interventions on hand-grip strength and completion time in 50-m freestyle swim drills in order for swimmers with EP to return to this sport.

The neighbourhood built environment and health-related fitness: a narrative systematic review

Background

There is increasing evidence demonstrating the importance of the neighbourhood built environment in supporting physical activity. Physical activity provides numerous health benefits including improvements in health-related fitness (i.e., muscular, cardiorespiratory, motor, and morphological fitness). Emerging evidence also suggests that the neighbourhood built environment is associated with health-related fitness. Our aim was to summarize evidence on the associations between the neighbourhood built environment and components of health-related fitness in adults.

Methods

We undertook a systematic review following PRISMA guidelines. Our data sources included electronic searches in MEDLINE, Embase, CINAHL, Web of Science, SPORTDiscus, Environment Complete, ProQuest Dissertations and Theses, and Transport Research International Documentation from inception to March 2021. Our eligibility criteria consisted of observational and experimental studies estimating associations between the neighbourhood built environment and health-related fitness among healthy adults (age ≥ 18 years). Eligible studies included objective or self-reported measures of the neighbourhood built environment and included either objective or self-reported measures of health-related fitness. Data extraction included study design, sample characteristics, measured neighbourhood built environment characteristics, and measured components of health-related fitness. We used individual Joanna Briggs Institute study checklists based on identified study designs. Our primary outcome measure was components of health-related fitness (muscular; cardiorespiratory; motor, and morphological fitness).

Results

Twenty-seven studies (sample sizes = 28 to 419,562; 2002 to 2020) met the eligibility criteria. Neighbourhood destinations were the most consistent built environment correlate across all components of health-related fitness. The greatest number of significant associations was found between the neighbourhood built environment and morphological fitness while the lowest number of associations was found for motor fitness. The neighbourhood built environment was consistently associated with health-related fitness in studies that adjusted for physical activity.

Conclusion

The neighbourhood built environment is associated with health-related fitness in adults and these associations may be independent of physical activity. Longitudinal studies that adjust for physical activity (including resistance training) and sedentary behaviour, and residential self-selection are needed to obtain rigorous causal evidence for the link between the neighbourhood built environment and health-related fitness.

Trial registration

Protocol registration: PROSPERO number CRD42020179807.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12966-022-01359-0.

Electrode Size and Placement for Surface EMG Bipolar Detection from the Brachioradialis Muscle: A Scoping Review

The brachioradialis muscle (BRD) is one of the main elbow flexors and is often assessed by surface electromyography (sEMG) in physiology, clinical, sports, ergonomics, and bioengineering applications. The reliability of the sEMG measurement strongly relies on the characteristics of the detection system used, because of possible crosstalk from the surrounding forearm muscles. We conducted a scoping review of the main databases to explore available guidelines of electrode placement on BRD and to map the electrode configurations used and authors’ awareness on the issues of crosstalk. One hundred and thirty-four studies were included in the review. The crosstalk was mentioned in 29 studies, although two studies only were specifically designed to assess it. One hundred and six studies (79%) did not even address the issue by generically placing the sensors above BRD, usually choosing large disposable ECG electrodes. The analysis of the literature highlights a general lack of awareness on the issues of crosstalk and the need for adequate training in the sEMG field. Three guidelines were found, whose recommendations have been compared and summarized to promote reliability in further studies. In particular, it is crucial to use miniaturized electrodes placed on a specific area over the muscle, especially when BRD activity is recorded for clinical applications.

Ergogenic effects of lifting straps on movement velocity, grip strength, perceived exertion and grip security during the deadlift exercise

It is possible that during resistance training, a weak link in the kinetic chain could possibly result in under-stimulated prime movers. Since grip strength can be a limiting factor during multiple sets of various pulling exercises such as deadlifts, it is important to determine how lifting straps can affect mechanical performance, grip strength, perceived exertion and perceived grip security and power. Sixteen males (24.4 ± 2.3 y; 181.6 ± 5.8 cm; 86.6 ± 8.2 kg) completed three protocols: 4 sets of 4 repetitions without straps using 80% of their without-straps 1-repetition max (DLnn); the same protocol with straps based on their without-straps 1-repetition max (DLwn); and the same with straps based on their with-straps 1-repetitions max (DLww). DLwn allowed for greater mean velocity (MV) and peak velocity (PV) than DLnn and DLww, while MV and PV were greater during DLnn than DLww. The magnitude of grip fatigue was lower during DLwn and DLww than DLn. Perceived grip security and power were greater during DLwn and DLww compared to DLn. Perceived exertion was lower during DLwn than DLnn and DLww. These findings suggest that the use of lifting straps during deadlifts allows for a better maintenance of grip strength, faster grip strength recovery following training, and greater perceived grip security and power than deadlifts performed without lifting straps, while also increasing mechanical performance and decreasing the perceived exertion. Therefore, the ergogenic potential of the lifting straps has important training implications and should be considered during RT involving the deadlift exercise and possibly other pulling exercises.

The Use of Lifting Straps Alters the Entire Load-Velocity Profile During the Deadlift Exercise

Jukic, I, García-Ramos, A, Malecek, J, Omcirk, D, and Tufano, JJ. The use of lifting straps alters the entire load-velocity profile during the deadlift exercise. J Strength Cond Res 34(12): 3331-3337, 2020-This study aimed to compare the one repetition maximum (1RM) and load-velocity (LV) profile between deadlifts performed with (DLw) and without (DLn) lifting straps. The full individual LV relationship of 20 men (age: 24.3 ± 2.4 years; body height: 180.6 ± 6.9 cm; body mass: 85.8 ± 8.0 kg) was randomly evaluated during 2 separate sessions for the DLw and DLn via an incremental loading test. One repetition maximum was greater (p < 0.001; g = 0.56, 95% confidence interval = [0.32, 0.79]) for DLw (177.0 ± 28.9 kg) compared with DLn (160.6 ± 26.0 kg). A highly linear relationship between mean velocity (MV) and %1RM was observed for both conditions (R > 0.95; SEE < 6.18 %1RM for pooled data and R > 0.98; SEE < 3.6 %1RM for individual data). However, MV associated with each %1RM was greater for DLn, and these differences were accentuated as the loading magnitude increased (g = 0.30-1.18). One repetition maximum was strongly associated between both conditions (r = 0.875 [0.71, 0.95]), whereas MV at 1RM (r = 0.21 [-0.25, 0.60]) was unrelated between conditions. The slope of the LV profiles (r = 0.845 [0.64, 0.94]) was correlated, but differed (g = 0.41 [0.16, 0.66]) between DLw and DLn, whereas the mean test velocity of all loads was unrelated (r = 0.270 [-0.20, 0.64]). An individual LV profile should be created for each athlete in the same condition that are going to be used in training to obtain a more precise estimation of the submaximal relative loads.