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Strength Testing—Predicting a One-Rep Max from Reps-to-Fatigue
Journal of Physical Education, Recreation & Dance
... The one-repetition maximum (1RM) was calculated according to the protocol of Brzycki (1993) [18]. According to this protocol, participants executed repetitions with the appropriate speed and range of motion until reaching failure. ...
... The one-repetition maximum (1RM) was calculated according to the protocol of Brzycki (1993) [18]. According to this protocol, participants executed repetitions with the appropriate speed and range of motion until reaching failure. ...
... Then, the weight was adjusted until the subject could only complete 4-6 maximum repetitions. The test concluded at this point, and we computed the 1RM using Brzycki's formula [18]. ...
Purpose
The present study explores the synergistic impact of tDCS and low-intensity exercise with practical blood flow restriction on the thickness, strength, and electrical activity of the biceps brachii muscle.
Methods
The study involved 44 healthy young men, divided into four groups: tDCS-pBFR (n = 11), Sham-pBFR (sham-tDCS) (n = 9), tDCS (n = 10), and control (n = 8). Six participants were unable to complete the exercises. Anodal tDCS was applied over the M1 with an intensity of 1.5 (mA). The participants executed dumbbell curls for the biceps at 80% of their 1RM. Following initial assessments, a covariance analysis was performed. The researchers measured biceps muscle strength, volume, and electromyography activity.
Results
The results found that the increase in arm muscle circumference was significant in the groups that performed pBFR exercises (p < 0.05), regardless of whether tDCS was applied or not. We observed no significant difference in strength and electromyography between the tDCS-pBFR and Sham-pBFR groups.
Conclusions
The present study provides experimental evidence of the lack of synergistic effects of using tDCS in combination with low-intensity exercises with practical blood flow restriction after 4 weeks of training.
... Considering that the potential risk of skeletal muscle injury is associated with standard 1RM tests in older individuals, KES was evaluated using an estimated 1RM 23 . Following the measurement protocol reported by Brzycki et al. 24 , the subjects underwent a test whilst seated on an extensor chair equipped with a weight plate measured in kilograms. Initially, the weight plate load was adjusted at 45% BM for females and 64% for males 25 . ...
... A high weight was applied for testing if the subjects could perform more than 10 repetitions; otherwise, a submaximal weight was used. The 1RM value was estimated using the following formula: estimated 1RM (kg) = submaximal weight (kg) / (1.0278 − 0.0278 × maximal number of repetitions) 24 . ...
Low-load resistance training with blood flow restriction (LRT-BFR) has shown potential to improve muscle strength and mass in different populations; however, there remains limited evidence in sarcopenic people diagnosed with sarcopenia criteria. This study systematically compared the effectiveness of LRT-BFR and conventional high-intensity resistance training (CRT) on clinical muscle outcomes (muscle mass, strength and performance), cardiovascular disease (CVD) risk factors and sarcopenia-related biomarkers of older people with sarcopenia. Twenty-one older individuals (aged 65 years and older) diagnosed with sarcopenia were randomly assigned to the LRT-BFR (20%–30% one-repetition maximum (1RM), n = 10) or CRT (60%–70% 1RM, n = 11) group. Both groups underwent a supervised exercise program three times a week for 12 weeks. The primary outcome was knee extensor strength (KES), and the secondary outcomes included body composition (body mass, body mass index and body fat percentage), muscle mass [appendicular skeletal muscle mass index (ASMI)], handgrip strength, physical performance [short physical performance battery (SPPB) and 6-m walk], CVD risk factors [hemodynamic parameters (systolic and diastolic blood pressure and heart rate (SBP, DBP and HR)) and lipid parameters (total cholesterol, triglyceride (TG), high-density lipoprotein (HDL) and low-density lipoprotein)], sarcopenia-related blood biomarkers [inflammatory biomarkers, hormones (growth hormone (GH) and insulin-like growth factor 1) and growth factors (myostatin and follistatin)] and quality of life [Short Form 36 Health Survey (SF-36)]. Both interventions remarkably improved the body composition, KES, 6-m walk, SBP, HDL, TG, GH, FST and SF-36 scores. CRT significantly improved the ASMI (p < 0.05) and SPPB (p < 0.05). A significant improvement in HR was observed only after LRT-BFR. No significant between-group differences were found before and after the interventions. This study suggested that LRT-BFR and CRT are beneficial to the clinical muscle outcomes, CVD risk factors and certain sarcopenia-related biomarkers of older people with sarcopenia. By comparison, CRT seems more effective in improving muscle mass, while LRT-BFR may be more beneficial for improving cardiovascular health in this population. Therefore, LRT-BFR is a potential alternative to CRT for aging sarcopenia.
... Patients who participated in the BEATE trial also performed butterfly reverse each TS and anteversion or retroversion of the shoulder every other TS. Each exercise was conducted for 1 to 3 sets with 12 repetitions at 60-80% of their hypothetical one repetition maximum, estimated with the Brzycki formula [7]. The training schedule followed a progressive approach, in which the applied load was increased by at least 5% if the prescribed load was successfully lifted for 3 sets of 12 repetitions in three consecutive TS. ...
Purpose
In resistance training (RT), the change in volume-load from training sessions (TS) to TS is an indicator of training progress. Resulting growth trajectories are likely to differ between individuals. Understanding this variation is important for exercise planning in general, but even more for clinical populations. We investigated this variation in breast cancer patients undergoing treatment.
Methods
Data of 69 patients from two randomized controlled trails were investigated. They conducted a 12-week RT program. We fitted a quadratic Bayesian regression model to the baseline standardized volume-load over the course of the intervention. We allowed all parameters to vary both between exercises and between individuals.
Results
We observed a positive linear component of 0.093 (95% uncertainty interval (UI) 0.058 to 0.120) and a negative quadratic component of − 0.002 (95% UI -0.008 to 0.001) for the mean trajectory of the change in volume-load. For the different exercises, we observed a dispersion for both the linear (0.043, 95% UI 0.018 to 0.082) and the quadratic component (0.002, 95% UI < 0.001 to 0.004). Variation between individual appears to be approximately four times larger. We also observed between-exercise variation within individuals. Extrapolation of the regression model indicates training progression stagnates after 20.6 TS (95% UI 14.8 to 44.4).
Conclusion
There is substantial variation in RT response between breast cancer patients undergoing tumor therapy and in-between exercises. The non-linear trajectory indicates that training progression will eventually plateau, demanding periodization and timely modification.
Trial registration
BEATE Study: NCT01106820, Date: April 20, 2010; BEST Study: NCT01468766, Date: November 9, 2011.
... El pretest I consistió en una prueba de RM indirecto en sentadilla que se calculó con la fórmula de brzycki (Brzycki, 1993), el pretest II consistió en un salto contra movimiento (CMJ) que fue analizado por medio de la plataforma de Fuerza AMTI600600, con frecuencia de muestreo de 1000Hz y asociado a ello fueron procesados videos por la aplicación My Jump 2 de Carlos Balsalobre (Balsalobre-Fernández, 2015) y el pretest III fue una prueba de 60 metros salida detenida en campo abierto. ...
Este estudio determino el impacto de un programa de entrenamiento destinado a mejorar la potencia mediante la sentadilla profunda y la media sentadilla. Participaron nueve atletas registrados en la Liga Vallecaucana de Ciclismo. Se realizaron mediciones de tiempo en una distancia de 60 metros con salida detenida en bicicleta, así como el salto contra movimiento (CMJ) y la repetición máxima (RM) antes y después de un periodo de entrenamiento de 4 semanas. Los participantes se distribuyeron en tres grupos: el grupo 1 realizó la media sentadilla, el grupo 2 llevó a cabo la sentadilla profunda, y el grupo 3 se sometió a ambos ejercicios. Se observaron cambios significativos en los valores de tiempo en los 60 metros para el grupo 2, que mejoró (de 9.35 s ± 1.18 s a 9.19 s ± 1.19 s), en contraste con los otros dos grupos que no experimentaron mejoras significativas. El grupo 2 también mostró mejoras en los valores de CMJ (de 37.24 cm ± 6.22 cm a 40.75 cm ± 5.12 cm), al igual que el grupo 3 (de 33.17 cm ± 3.12 cm a 35.07 cm ± 5.56 cm). En cambio, el grupo 1 no presentó mejorías en estos resultados. En cuanto a la RM, todos los grupos superaron sus marcas iniciales. En resumen, el ejercicio de sentadilla profunda demostró ser más efectivo para mejorar el rendimiento en todas las pruebas, incluso con un periodo de entrenamiento breve, independientemente del ángulo de ejecución del ejercicio.
Background and Purpose: Myostatin and follistatin are key proteins in muscle tissue regulation, growth,
and hypertrophy. This study aimed to investigate the effects of two types of resistance training on the serum
levels of myostatin and follistatin and the ratio of follistatin to myostatin in healthy young men.
Materials and Methods: Twenty active young men were randomly divided into two equal groups of
pyramid resistance exercises (, Mean±SD; age, 22.3±4.7 years; body mass index, 23.1±3.9 kg/m2; fat
percentage, 27.6±10.7) and inverted pyramid resistance exercises (Mean±SD; age, 21.11±3.55 years; body
mass index, 23.2±6.7 kg/m2; fat percentage, 26.3±13.8). The training lasted for eight weeks and three
sessions per week. Each training session included six movements of chest press, leg press, barbell curl,
triceps extensions, leg flexions, and leg extensions at an intensity corresponding to 100-50% of one
maximum repetition in the pyramid resistance training group and at an intensity of 50-100% of one
maximum repetition in the inverted pyramid resistance training group. Data analyses were carried out by
using dependent t-test and ANCOVA at a significance level of P≤ 0.05.
Results: Data analyses showed that eight weeks of pyramid and inverted pyramid resistance training caused
a significant decrease in the serum level of myostatin (P=0.004,P=0.01, respectively) and a significant increase
in the serum level of follistatin (p = 0.001, P=001), and the ratio of follistatin to myostatin (P=0.001, P=0.001)
in healthy men. The results for ANCOVA analyses showed that there is no significant difference between the
two groups for serum levels of myostatin, follistatin, and the ratio of follistatin to myostatin (p>0.05).
Conclusion: Pyramid and reverse pyramid resistance training were associated with an increase in
follistatin, the ratio of follistatin to myostatin, and a decrease in myostatin. Since, we found no significant
difference between the experimental groups, it could be concluded that in young men these training
protocols may lead to muscular hypertrophy similarly.
Keywords: Resistance Training, Pyramid Resistance Training, Inverted Pyramid Resistance Training,
Myostatin, Follistatin
How to cite this article: Cherag Birjandi S, Farhadpour M. Comparison of the effects of two types of
resistance training on the serum levels of factors involved in muscular hypertrophy in healthy young men. J
Sport Exerc Physiol. 2024; 17(2):67-79
Introdução: O treinamento de força é importante na preparação física de atletas. No voleibol de praia de alto rendimento muitos movimentos de potência são realizados ao longo do jogo e da preparação física. Objetivo: Analisar a influência do treinamento de força combinado com exercícios explosivos na capacidade neuromuscular em atletas. Metodologia: Seis atletas do sexo feminino foram treinaram durante 3 meses. Foram mensuradas a massa corporal, estatura e calculado o Indice de Massa Corporal. Os testes aplicados unilateralmente e bilateralmente foram avaliados através da plataforma de salto Elite Jump. Resultado: Houve uma diminuição da massa corporal, podendo ter influenciado nos resultados dos saltos. O salto que teve maior influência do treinamento foi o Horizontal Bilateral e Unilateral. Conclusão: O treinamento de força em conjunto com exercícios explosivos aumentou a potência no santo horizontal. Porém, não houve alteração nos demais saltos.
Purpose
This study investigated the impact of the equated volume load on three different resistance training methods (traditional, pre-exhaustion, and drop sets) on muscle strength, endurance, and hypertrophy in young men.
Methods
Fifty-three recreationally trained men performed a 1-week familiarization and were randomized into three groups: traditional (TRT, n = 18), pre-exhaustion (Pre-Ex, n = 17), and drop set (DS, n = 18). All groups were enrolled in a 6-week, twice-weekly intervention program. The TRT performed four sets of 8–12 repetitions with 70%1RM for each leg press and leg extension exercises, with 3-min rest between sets. The Pre-Ex performed leg extensions with 30%1RM until exhaustion before each exercise, while the DS performed leg extensions with 30%1RM after the last set of each exercise. We collected data from 1RM leg press and a 5RM leg extension, isometric strength, muscular endurance, and muscle thickness.
Results
Results revealed that all training methods had significant improvements in muscle strength (p < 0.001), endurance (p < 0.001), and hypertrophy (p < 0.001), with no significant difference between groups (p > 0.05).
Conclusion
Therefore, the TRT, Pre-Ex, and DS methods revealed to be equally effective on enhancing muscle strength, endurance, and hypertrophy. Thus, the study did not support the superiority of pre-exhaustion or drop set over traditional resistance training when the volume is equated.
Objective This quasi-experimental parallel pilot study aimed to analyse the feasibility and effectiveness of a multicomponent physical exercise programme (MPEP) among community-dwelling older adults who were users of home care services (HCS). Methods Forty-four participants were allocated to a MPEP group or a control (CON) group based on choice. Participants in the MPEP group performed individualised and progressive strength, balance and flexibility exercises three times per week for 16 weeks. One session was a group face-to-face session guided by a physical therapist, and the other two were individual home-based sessions following the Vivifrail programme. Feasibility was assessed via recruitment, adherence, safety and acceptability. Physical performance; nutritional, psycho-affective and cognitive status; and frailty were measured at baseline and after the intervention. Results Among the 604 eligible participants, 44 consented to participate. Completion rate was 7%. A total of 83% of participants attended face-to-face sessions with a compliance rate of 73%. Reported compliance with at-home sessions was 71%. No dangerous adverse events were reported. The participants reported an average satisfaction of 9 out of 10. Group-by-time interactions in favour of the MPEP group were found for the Short Physical Performance Battery ( p =0.024) and Fried Frailty Scale ( p =0.019). The MPEP group showed a decrease in the number of frail participants according to the Fried Frailty Scale ( p =0.020) and the Short Physical Performance Battery ( p =0.050). There were no other group-by-time interactions. Conclusions The MPEP is feasible and effective at improving physical performance and frailty status among community-dwelling older adults who are users of HCS (NCT05726214 in the ClinicalTrials.gov registry).
We interpret the currently available scientific evidence to indicate that strength training should be as specific as possible. The coach or athlete, in designing a strength training programme, should attempt to have the training exercises similate the sport movement as closely as possible, in relation to movement pattern, velocity of movement, muscular contraction type, and contraction force. In the case of sport movements that are performed at high velocity, supplementary training at low velocity may be necessary to induce maximal adaptation within the muscles. Supplementary training with maximal or near maximal eccentric contractions may be beneficial in training for many sports because the large forces generated during this kind of training will stimulate maximal adaptation within the muscles. However, consideration should be given to the greater risk of injury that is associated with eccentric training. Failure to be specific in strength training may result in more than a poor return on the training investment; it may even be counter-productive. For example, the development of increased mass in irrelevant muscle groups may be detrimental in sports which demand a high strength to body mass ratio.