Including the Eccentric Phase in Resistance Training to Counteract the Effects of Detraining in Women: A Randomized Controlled Trial

Eccentric Exercise Guidelines for Managing Rheumatoid Arthritis: Findings From a Randomized Controlled Trial

Background and Aims

There are strong indications that the prevalence of poor body composition in RA patients is reportedly high. Evidence in the literature suggests that RA patients have low functional ability, which may negatively impact their work productivity and physical activity levels. Given the beneficial effects of an eccentric exercise intervention on RA conditions, there is still no sufficient information about the eccentric exercise guidelines for managing RA. This study aimed to develop eccentric exercise guidelines for managing RA conditions.

Methods

Eccentric exercise guidelines for managing RA were developed in three phases: A scoping literature review, an experimental pretest-posttest randomized control trial, and synthetization of the outcomes. Thirty-seven RA patients participated in the experimental pretest-posttest study and were randomized into control and exercise groups.

Results

Eccentric exercise interventions show positive effects on body composition, blood pressure, work-related performance, and physical activity levels in RA patients. Proposed management guidelines for RA conditions include 40-min eccentric exercises three times weekly. It is proposed that an eccentric exercise intervention should be progressive to elicit maximum benefits for RA patients.

Conclusion

An eccentric-concentrated exercise intervention is safe and provides a specific exercise trajectory for managing RA conditions. Evidence-based eccentric guidelines were developed to improve RA patients' body composition, physical activity levels, and cardiovascular risk factors. The guidelines could also benefit physical functioning and work productivity in RA patients. It should be used alongside the existing guidelines for managing RA disease conditions.

The effect of percussion massage therapy on the recovery of delayed onset muscle soreness in physically active young men-a randomized controlled trial

Background

Delayed onset muscle soreness (DOMS) is a common condition among physically active individuals, often resulting in reduced performance and discomfort. Although percussive massage treatment (PMT) is widely used as a recovery tool, there is limited evidence supporting its efficacy compared to traditional methods such as static stretching.

Objective

To investigate the effect of PMT on recovery from DOMS in physically active young men.

Methods

Thirty physically active male college students were randomized into three groups: static stretching (SS) group, a short-duration PMT (S-PMT) group, and a long-duration PMT (L-PMT) group. All participants performed squats to induce DOMS, followed by interventions of static stretching, 25 min of PMT, or 40 min of PMT, respectively. Measurements included the visual analog scale (VAS) pain score, knee joint range of motion (ROM), countermovement jump (CMJ), and integrated electromyography (iEMG). These were measured at baseline (P0), post-DOMS protocol (P1), post PMT (P2), 24 h post-intervention (P3), and 48 h post-intervention (P4). Data were analyzed using repeated-measures ANOVA or nonparametric tests, with multiple comparisons conducted at a significance level of p < 0.05.

Results

Compared with the SS and S-PMT group, the L-PMT group at P4 demonstrated significantly greater jump height (SS group: p < 0.001, d = 8.691; S-PMT group: p = 0.006, d = 4.37), peak ground reaction force (SS group: p < 0.001, d = 19.174; S-PMT group: p < 0.001, d = 14.334), and propulsion impulse (SS group: p < 0.001, d = 8.302; S-PMT group: p = 0.003, d = 4.517) during the CMJ propulsion phase. Additionally, the normalized iEMGs of the three muscles in the L-PMT group were significantly lower than those in the S-PMT (VM: p < 0.001, d = -5.692; RF: p < 0.001, d = -8.222; VL: p < 0.001, d = -10) and SS groups at P4 (VM: p < 0.001, d = -12; RF: p < 0.001, d = -11.384; VL: p < 0.001, d = -15). At P4, the L-PMT group exhibited significantly lower VAS scores than the SS group (p = 0.003, d = -1.53), as well as significantly greater knee joint ROM compared to the SS group (p = 0.012,d = 4.77).

Conclusion

PMT was more effective than static stretching for DOMS recovery. Furthermore, two 40-min PMT sessions provided greater benefits than two 25-min sessions for treating DOMS. These findings suggest that PMT can be a valuable tool for physically active individuals seeking to enhance recovery and maintain performance.

Clinical trial registration

The study was registered on ClinicalTrials.gov on September 21, 2024, with the identifier number NCT06612502.

The Effects of Reverse Nordic Exercise Training on Measures of Physical Fitness in Youth Karate Athletes

Background: In karate, the ability to execute high-velocity movements, particularly kicks and punches, is heavily dependent on the strength and power of the lower limb muscles, especially the knee extensors. As such, this study aimed to evaluate the effects of an 8-week eccentric training program utilizing the reverse Nordic exercise (RNE) integrated into karate training compared with regular karate training only on measures of physical fitness in youth karate athletes. Methods: Twenty-seven youth karatekas were recruited and allocated to either RNE group (n = 13; age = 15.35 ± 1.66 years; 7 males and 6 females) or an active control group ([CG]; n = 14; 7 males and 7 females; age = 15.30 ± 1.06 years). To track the changes in measures of physical fitness before and after training, tests to assess linear sprint speed (i.e., 10 m), change of direction (CoD) speed (i.e., modified 505 CoD), vertical jumping (i.e., countermovement jump [CMJ] height) and horizontal jumping distance (i.e., standing long jump [SLJ]), and lower-limb asymmetry score (i.e., the difference between SLJ-dominant and non-dominant legs) were carried out. Results: The results indicated significant group-by-time interactions in all measures of physical fitness (effect size [ES] = 1.03 to 2.89). Post-hoc analyses revealed significant changes in the RNE group across all performance measures (effect size [ES] = 0.33 to 1.63). Additionally, the asymmetry score exhibited a moderate decrease from pre to posttest (∆46.96%, ES = 0.64). In contrast, no significant changes were observed in the CG across all fitness measures. Moreover, the individual response analysis indicated that more karatekas from the RNE group consistently achieved improvements beyond the smallest worthwhile change threshold across all fitness measures. Conclusions: In summary, RNE training is an effective approach to enhance various physical fitness measures besides lower-limb asymmetry scores in youth karatekas and is easy to incorporate into regular karate training. Practitioners are therefore encouraged to consistently integrate RNE training to enhance essential physical fitness components in young karatekas.

Effects of detraining on neuromuscular function and structural adaptations following once- or twice-weekly eccentric resistance training in older adults

BACKGROUND

Eccentric resistance training elicits greater preservation of training-induced muscular adaptations compared with other training modalities, however the detraining profiles of different training dosages remain unknown.

AIMS

To examine the detraining effects following once- or twice-weekly eccentric-specific resistance training in older adults.

METHODS

Twenty-one older adults (age = 70.5 ± 6.0 year) completed a 12-week detraining period following the 12-week eccentric training programmes with neuromuscular function and muscle structure assessed six (mid-detraining) and 12 (post-detraining) weeks following training cessation.

RESULTS

From post-training to post-detraining, no significant regression of the training-induced improvements (collapsed group data reported) occurred in power (0%), strength (eccentric = 0%, isometric = 39%), or explosive strength over numerous epochs (0-32%), resulting in values that remained significantly greater than at pre-training. However, significant regression in the improvements in muscle thickness (91%) and fascicle angle (100%) occurred, resulting in values that were not significantly greater than pre-training.

DISCUSSION

The limited regression in neuromuscular function following a 12-week detraining period has important implications for supporting eccentric exercise prescription in older adults who often face periods of inactivity. However, further work is required to develop an effective maintenance dosage strategy that preserves improvements in muscle structure.

CONCLUSIONS

Eccentric resistance training elicits improvements in the neuromuscular function of older adults, which are sustained for at least 12 weeks after eccentric training cessation.

High Velocity Passive Stretching Mimics Eccentric Exercise in Cerebral Palsy and May Be Used to Increase Spastic Muscle Fascicle Length

Muscle fascicles are shorter and stiffer than normal in spastic Cerebral Palsy (CP). Increasing fascicle length (FL) has been attempted in CP, the outcomes of which have been unsatisfactory. In healthy muscles, FL can be increased using eccentric exercise at high velocities (ECC). Three conditions are possibly met during such ECC: muscle micro-damage, positive fascicle strain, and momentary muscle deactivation during lengthening. Participants with and without CP underwent a single bout of passive stretching at (appropriately) high velocities using isokinetic dynamometry, during which we examined muscle and fascicle behaviour. Vastus lateralis (VL) FL change was measured using ultrasonography and showed positive fascicle strain. Measures of muscle creatine kinase were used to establish whether micro-damage occurred in response to stretching, but the results did not confirm damage in either group. Vastus medialis (VM) and biceps femoris muscle activity were measured using electromyography in those with CP. Results supported momentary spastic muscle deactivation during lengthening: all participants experienced at least one epoch (60 ms) of increased activation followed by activation inhibition/deactivation of the VM during knee flexion. We argue that high-velocity passive stretching in CP provides a movement context which mimics ECC and could be used to increase spastic FL with training.

Moderators of Resistance Training Effects in Healthy Young Women: A Systematic Review and Meta-analysis

ABSTRACT

Molinari, T, Radaelli, R, Rech, A, Brusco, CM, Markarian, AM, and Lopez, P. Moderators of resistance training effects in healthy young women: A systematic review and meta-analysis. J Strength Cond Res 38(4): 804-814, 2024-To systematically review and analyze the effects of resistance-based exercise programs and potential moderators of change in body fat percentage, whole-body fat and lean mass, muscle hypertrophy, muscle strength, and muscle power/rapid force in healthy young women (between 18 and 35 years). A systematic search was undertaken in 7 databases from inception to May 2022. Eligible randomized controlled trials examined the effects of resistance-based exercise programs on outcomes of interest in healthy young women. Meta-analysis was undertaken with a 3-level mixed-effects model. Associations between standardized mean difference (SMD) and potential moderators (number of sessions, weekly volume, and intensity) were tested by meta-regression models. Statistical significance was set at an α level of 0.05, whereas an α level of 0.05-0.10 was also considered for potential moderators of resistance training effects. Forty articles ( n = 1,312) were included. Resistance-based exercise programs resulted in a significant improvement of 0.4 SMD (95% confidence intervals [95% CI]: 0.2 to 0.5, p < 0.001) in lean mass/muscle hypertrophy and 1.2 SMD (95% CI: 0.9 to 1.5, p < 0.001) in muscle strength. A higher number of sessions was associated with changes in lean mass/muscle hypertrophy ( β = 0.01 ± 0.00, p = 0.009), whereas a higher weekly volume approached statistical significance to moderate changes in muscle strength ( β = 0.01 ± 0.01, p = 0.053). Body fat percentage (-0.4 SMD, 95% CI: -0.6 to -0.1, p = 0.006) and muscle power/rapid force (0.6 SMD, 95% CI: 0.2 to 1.1, p = 0.011) were significantly improved. In conclusion, a higher resistance training volume was associated with greater improvements in lean mass/muscle hypertrophy, muscle strength, and body fat percentage, whereas muscle power/rapid force improvements were observed irrespective of prescription characteristics. These findings may help in designing resistance training programs for muscle hypertrophy, strength and power, and body fat percentage in healthy women.

High-Density Electromyography Excitation in Front vs. Back Lat Pull-Down Prime Movers

The current study compared the spatial excitation of the primary muscles during the lat pull-down exercise with the bar passing in front (front-LPD) or behind the neck (back-LPD) using high-density electromyography. Fourteen resistance trained men performed a front-LPD or a back-LPD within a non-fatiguing set with 8-RM as the external load. The muscle excitation centroid of latissimus dorsi, middle trapezius, pectoralis major, biceps brachii, triceps brachii and posterior deltoid muscles were recorded during the ascending and the descending phase. During the descending phase, the front-LPD showed superior excitation of the latissimus dorsi (ES = 0.97) and the pectoralis major (ES = 1.17), while in the ascending phase, the back-LPD exhibited superior excitation of the latissimus dorsi (ES = 0.63), and the front-LPD showed superior excitation of the biceps brachii (ES = 0.41) and the posterior deltoid (ES = 1.77). During the descending phase, the front-LPD showed a more lateral centroid of the latissimus dorsi (ES = 0.60), the biceps brachii (ES = 0.63) and the triceps brachii (ES = 0.98), while the centroid was more medial for the middle trapezius (ES = 0.58). The centroid of the middle trapezius was also more medial in the front-LPD during the ascending phase (ES = 0.85). The pectoralis major centroid was more cranial in the front-LPD for both the descending (ES = 1.58) and the ascending phase (ES = 0.88). The front-LPD appears to provide overall greater excitation in the prime movers. However, distinct spatial excitation patterns were observed, making exercise suitable for the training routine.

Biceps Brachii and Brachioradialis Excitation in Biceps Curl Exercise: Different Handgrips, Different Synergy

The current study analyzed the excitation of biceps brachii, brachioradialis, and anterior deltoid during bilateral biceps curl performed with different handgrips. Ten competitive bodybuilders performed bilateral biceps curl in non-exhaustive 6-rep sets using 8-RM with the forearm in supinated, pronated, and neutral positions. The ascending and descending phase of each variation was separately analyzed using the normalized root mean square collected using surface electromyography. During the ascending phase, (i) biceps brachii excitation was greater with the supinated compared to the pronated [+19(7)%, ES: 2.60] and neutral handgrip [+12(9)%, ES: 1.24], (ii) the brachioradialis showed greater excitation with the supinated compared to the pronated [+5(4)%, ES: 1.01] and neutral handgrip [+6(5)%, ES: 1.10], (iii) the anterior deltoid excitation was greater with the pronated and neutral handgrip compared to the supinated condition [+6(3)% and +9(2)%, ES: 2.07 and 3.18, respectively]. During the descending phase, the anterior deltoid showed greater excitation in the pronated compared to the supinated handgrip [+5(4)%, ES: 1.02]. Changing the handgrips when performing biceps curl induces specific variations in biceps brachii and brachioradialis excitation and requires different anterior deltoid interventions for stabilizing the humeral head. Practitioners should consider including different handgrips in the biceps curl routine to vary the neural and mechanical stimuli.

Bilateral Biceps Curl Shows Distinct Biceps Brachii and Anterior Deltoid Excitation Comparing Straight vs. EZ Barbell Coupled with Arms Flexion/No-Flexion

The present study investigated the excitation of the biceps brachii and anterior deltoid during bilateral biceps curl performed using the straight vs. EZ barbell and with or without flexing the arms. Ten competitive bodybuilders performed bilateral biceps curl in non-exhaustive 6-rep sets using 8-RM in four variations: using the straight barbell flexing (ST_flex) or not flexing the arms (ST_no-flex) or the EZ barbell flexing (EZ_flex) or not flexing the arms (EZ_no-flex). The ascending and descending phases were separately analyzed using the normalized root mean square (nRMS) collected using surface electro-myography. For the biceps brachii, during the ascending phase, a greater nRMS was observed in ST_no-flex vs. EZ_no-flex (+1.8%, effect size [ES]: 0.74), in ST_flex vs. ST_no-flex (+17.7%, ES: 3.93) and in EZ_flex vs. EZ_no-flex (+20.3%, ES: 5.87). During the descending phase, a greater nRMS was observed in ST_flex vs. EZ_flex (+3.8%, ES: 1.15), in ST_no-flex vs. ST_flex (+2.8%, ES: 0.86) and in EZ_no-flex vs. EZ_flex (+8.1%, ES: 1.81). The anterior deltoid showed distinct excitation based on the arm flexion/no-flexion. A slight advantage in biceps brachii excitation appears when using the straight vs. EZ barbell. Flexing or not flexing the arms seems to uniquely excite the biceps brachii and anterior deltoid. Practitioners should consider including different bilateral biceps barbell curls in their routine to vary the neural and mechanical stimuli.

Elevated muscle mass accompanied by transcriptional and nuclear alterations several months following cessation of resistance-type training in rats

Rodent studies investigating long-term effects following termination of hypertrophy-inducing loading have predominantly involved exposures such as synergist ablation and weighted wheel running or ladder climbing. This research yielded a spectrum of results regarding the extent of detraining in terms of muscle mass and myonuclei number. The studies were also limited in their lack of sensitive performance measures and indirect relatedness to resistance training. Our research group developed and validated a relevant rat model of resistance-type training that induces increased muscle mass and performance. The aim of the present study was to determine to what extent these features persist 3 months following the termination of this training. While performance returned to baseline, muscle mass remained elevated by 17% and a shift in distribution to larger muscle fibers persisted. A 16% greater total RNA and heightened mRNA levels of ribosomal protein S6 kinases implicated preserved transcriptional output and ribosomal content. Remodeling of muscle fiber nuclei was consistent with these findings - increased nuclear number and a distribution shift to a more circular nuclear shape. These findings indicate that muscle mass detrains at a slower rate than performance and implicates multiple forms of myonuclear remodeling in muscle memory.

Appropriate Reporting of Exercise Variables in Resistance Training Protocols: Much more than Load and Number of Repetitions

Manipulating resistance training variables is crucial to plan the induced stimuli correctly. When reporting the exercise variables in resistance training protocols, sports scientists and practitioners often refer to the load lifted and the total number of repetitions. The present conceptual review explores all within-exercise variables that may influence the strength and hypertrophic gains, and the changes in muscle architecture. Together with the (1) load and (2) the number of repetitions, (3) performing repetitions to failure or not to failure, (4) the displacement of the load or the range of movement (full or partial), (5) the portion of the partial movement to identify the muscle length at which the exercise is performed, (6) the total time under tension, the duration of each phase and the position of the two isometric phases, (7) whether the concentric, eccentric or concentric-eccentric phase is performed, (8) the use of internal or external focus and (9) the inter-set rest may all have repercussions on the adaptations induced by each resistance exercise. Manipulating one or more variable allows to increase, equalize or decrease the stimuli related to each exercise. Sports scientists and practitioners are invited to list all aforementioned variables for each exercise when reporting resistance training protocols.

Effects of Upper Body Eccentric versus Concentric Strength Training and Detraining on Maximal Force, Muscle Activation, Hypertrophy and Serum Hormones in Women

Effects of eccentric (ECC) versus concentric (CON) strength training of the upper body performed twice a week for 10 weeks followed by detraining for five weeks on maximal force, muscle activation, muscle mass and serum hormone concentrations were investigated in young women (n = 11 and n = 12). One-repetition bench press (1RM), maximal isometric force and surface electromyography (EMG) of triceps brachii (TB), anterior deltoid (AD) and pectoralis major (PM), cross-sectional area (CSA) of TB (Long (LoH) and Lateral Head (LaH)) and thickness of PM, as well as serum concentrations of free testosterone, cortisol, follicle-stimulating hormone, estradiol and sex hormone-binding globulin were measured. ECC and CON training led to increases of 17.2 ± 11.3% (p < 0.001) and 13.1 ± 5.7% (p < 0.001) in 1RM followed by decreases of -6.6 ± 3.6% (p < 0.01) and -8.0 ± 4.5% (p < 0.001) during detraining, respectively. Isometric force increased in ECC by 11.4 ± 9.6 % (p < 0.05) from week 5 to 10, while the change in CON by 3.9±6.8% was not significant and a between group difference was noted (p < 0.05). Maximal total integrated EMG of trained muscles increased only in the whole subject group (p < 0.05). CSA of TB (LoH) increased in ECC by 8.7 ± 8.0% (p < 0.001) and in CON by 3.4 ± 1.6% (p < 0.01) and differed between groups (p < 0.05), and CSA of TB (LaH) in ECC by 15.7 ± 8.0% (p < 0.001) and CON by 9.7 ± 6.6% (p < 0.001). PM thickness increased in ECC by 17.7 ± 10.9% (p < 0.001) and CON by 14.0 ± 5.9% (p < 0.001). Total muscle sum value (LoH + LaH + PM) increased in ECC by 12.4 ± 6.9% (p < 0.001) and in CON by 7.1 ± 2.9% (p < 0.001) differing between groups (p < 0.05) and decreased during detraining in ECC by -6.5 ± 4.3% (p < 0.001) and CON by -6.1 ± 2.8% (p < 0.001). The post detraining combined sum value of CSA and thickness was in ECC higher (p < 0.05) than at pre training. No changes were detected in serum hormone concentrations, but baseline free testosterone levels in the ECC and CON group combined correlated with changes in 1RM (r = 0.520, p < 0.016) during training. Large neuromuscular adaptations of the upper body occurred in women during ECC, and CON training in 10 weeks. Isometric force increased only in response to ECC, and total muscle sum value increased more during ECC than CON training. However, no changes occurred in serum hormones, but individual serum-free testosterone baseline concentrations correlated with changes in 1RM during strength training in the entire group. Both groups showed significant decreases in neuromuscular performance and muscle mass during detraining, while post detraining muscle sum value was only in ECC significantly higher than at pre training.

Adapted physical activity in subjects and athletes recovering from covid-19: a position statement of the Società Italiana Scienze Motorie e Sportive

Coronavirus disease 2019 (COVID-19) is a worldwide pandemic illness that is impacting the cardiovascular, pulmonary, musculoskeletal, and cognitive function of a large spectrum of the worldwide population. The available pharmacological countermeasures of these long-term effects of COVID-19 are minimal, while myriads of non-specific non-pharmacological treatments are emerging in the literature. In this complicated scenario, particular emphasis should be dedicated to specific exercise interventions tailored for subjects and athletes recovering from COVID-19. Specific guidelines on adapted physical activity in this critical population are unavailable so far, therefore, in this position statement of the Società Italiana di Scienze Motorie e Sportive (SISMeS) the members of the steering committee of the research group Attività Motoria Adattata, Alimentazione, Salute e Fitness have indicated the adapted physical activity approaches to counteract the long-term effects of the COVID-19, both in good health people and athletes.

The Eccentric Phase in Unilateral Resistance Training Enhances and Preserves the Contralateral Knee Extensors Strength Gains After Detraining in Women: A Randomized Controlled Trial

The current randomized controlled study investigated whether or not the inclusion of the eccentric phase in resistance training favors the contralateral strength gains after different unilateral protocols, and whether such gains are retained after detraining. Sixty healthy women were randomly assigned to a unilateral concentric-only (CONC), eccentric-only (ECC), concentric–eccentric (TRAD) volume-equated knee extension training or control group (CON). The participants trained 2 days/week for 8 weeks and then did not train for further 8 weeks. Knee extensors isokinetic concentric, eccentric, and isometric peak torque and vastus lateralis muscle thickness were assessed in the contralateral limb at baseline, post-training, and post-detraining. At post-training, concentric peak torque increased in CONC [+9.2%, 95%CI (+6.2/+12.3), p < 0.001, ES: 0.70, 95%CI (0.01/1.39)], ECC [+11.0% (+7.7/+14.2), p < 0.001: ES: 0.66(0.09/1.23)] and TRAD [+8.5%(+5.7/+11.6), p < 0.001, ES: 0.50(0.02/0.98)]. Eccentric peak torque increased in ECC in ECC [+15.0%(+11.4/+20.7), p < 0.001, ES: 0.91(0.14/1.63)] and TRAD [+5.5%(+0.3/10.7), p = 0.013, ES: 0.50(0.05/0.95)]. Isometric peak torque increased in ECC [+11.3(+5.8/16.8), p < 0.001, ES: 0.52(0.10/0.94)] and TRAD [+8.6%(+3.4/+13.7), p < 0.001, ES: 0.55(0.14/0.96)]. No change in eccentric and isometric peak torque occurred in CONC (p > 0.05). Muscle thickness did not change in any group (p > 0.05). At post-detraining, all groups preserved the contralateral strength gains observed at post-training (p < 0.05). The findings showed that ECC and TRAD increased contralateral knee extensors strength in concentric, eccentric, and isometric modality, while CONC only increased concentric strength. The eccentric phase appears to amplify the cross-education effect, permitting a transfer in strength gaining toward multiple testing modalities. Both eccentric-based and traditional eccentric–concentric resistance protocols are recommended to increase the contralateral retention in strength gains after a detraining period.

An Electromyographic Analysis of Romanian, Step-Romanian, and Stiff-Leg Deadlift: Implication for Resistance Training

The present study examined the posterior chain muscle excitation in different deadlift variations. Ten competitive bodybuilders (training seniority of 10.6 ± 1.8 years) performed the Romanian (RD), Romanian standing on a step (step-RD), and stiff-leg deadlift (SD) with an 80% 1-RM. The excitation of the gluteus maximus, gluteus medius, biceps femoris, semitendinosus, erector spinae longissimus, and iliocostalis was assessed during both the ascending and descending phases. During the ascending phase, the RMS of the gluteus maximus was greater in the step-RD than in the RD (effect size (ES): 1.70, 0.55/2.84) and SD (ES: 1.18, 0.11/2.24). Moreover, a greater RMS was found in the SD than in the RD (ES: 0.99, 0.04/1.95). The RMS of the semitendinosus was greater in the step-RD than in the RD (ES: 0.82, 0.20/1.44) and SD (ES: 3.13, 1.67/4.59). Moreover, a greater RMS was found in the RD than in the SD (ES: 1.38, 0.29/2.48). The RMS of the longissimus was greater in the step-RD than in the RD (ES: 2.12, 0.89/3.34) and SD (ES: 3.28, 1.78/4.78). The descending phase had fewer differences between the exercises. No further differences between the exercises were found. The step-RD increased the overall excitation of the posterior chain muscles, possibly because of the greater range of movement and posterior muscle elongation during the anterior flexion. Moreover, the RD appeared to target the semitendinosus more than the SD, while the latter excited the gluteus maximus more.