Effects Of Resistance Training Frequency Research Articles

A meta-regression of the effects of resistance training frequency on muscular strength and hypertrophy in adults over 60 years of age

ABSTRACT Resistance training is a commonly used strategy for improving both athletic performance and general health. While the contribution of resistance training intensity and volume to muscle strength and hypertrophy have been extensively investigated, training frequency only recently received sufficient attention, especially in older adults. A meta-regression was conducted to compare muscle strength and hypertrophic adaptations to resistance training programmes performed with different training frequencies in adults over 60 years of age. The systematic literature search identified 14 articles for meta-regression. For each outcome, an effect size (ES) was calculated as the pre-test-post-test change, divided by the pooled pre-test standard deviation (SD). Random-effects meta-regressions for multilevel data structures, using study as the clustering variable, were performed using package metafor in R. Maximal strength shows a significant effect of frequency (p = 0.001), with an increase in effect size of 0.14 for every day increase in frequency (CI: 0.08, 0.21). For muscle hypertrophy, no significant effect of frequency was found (p = 0.67). Considering that muscle hypertrophy was not affected, while maximum strength was only slightly improved with additional training days, it seems unlikely that more than two weekly resistance training sessions would provide any further benefits for older adults.

Effect of Resistance Training Frequency on Neuromuscular Performance and Muscle Morphology After 8 Weeks in Trained Men.

Brigatto, FA, Braz, TV, Zanini, TCdC, Germano, MD, Aoki, MS, Schoenfeld, BJ, Marchetti, PH, and Lopes, CR. Effect of resistance training frequency on neuromuscular performance and muscle morphology after 8 weeks in trained men. J Strength Cond Res 33(8): 2104-2116, 2019-The purpose of this study was to investigate the chronic effects of training muscle groups 1 day per week vs. 2 days per week on neuromuscular performance and morphological adaptations in trained men with the number of sets per muscle group equated between conditions. Participants were randomly assigned in 2 experimental groups: 1 session·wk per muscle group (G1, n = 10), where every muscle group was trained once a week with 16 sets or 2 sessions·wk per muscle group (G2, n = 10), where every muscle group was trained twice a week with 8 sets per session. All other variables were held constant over the 8-week study period. No significant difference between conditions for maximal strength in the back squat or bench press, muscle thickness in the elbow extensors, elbow flexors, or quadriceps femoris, and muscle endurance in the back squat and bench press performed at 60% 1 repetition maximum was detected. Effect size favored G2 for some outcome measurements, suggesting the potential of a slight benefit to the higher training frequency. In conclusion, both G1 and G2 significantly enhance neuromuscular adaptations, with a similar change noted between experimental conditions.

How many times per week should a muscle be trained to maximize muscle hypertrophy? A systematic review and meta-analysis of studies examining the effects of resistance training frequency

ABSTRACTTraining frequency is considered an important variable in the hypertrophic response to regimented resistance exercise. The purpose of this paper was to conduct a systematic review and meta-analysis of experimental studies designed to investigate the effects of weekly training frequency on hypertrophic adaptations. Following a systematic search of PubMed/MEDLINE, Scoups, and SPORTDiscus databases, a total of 25 studies were deemed to meet inclusion criteria. Results showed no significant difference between higher and lower frequency on a volume-equated basis. Moreover, no significant differences were seen between frequencies of training across all categories when taking into account direct measures of growth, in those considered resistance-trained, and when segmenting into training for the upper body and lower body. Meta-regression analysis of non-volume-equated studies showed a significant effect favoring higher frequencies, although the overall difference in magnitude of effect between frequencies of 1 and 3+ days per week was modest. In conclusion, there is strong evidence that resistance training frequency does not significantly or meaningfully impact muscle hypertrophy when volume is equated. Thus, for a given training volume, individuals can choose a weekly frequency per muscle groups based on personal preference.

Frequency of resistance training does not affect inhibitory control or improve strength in well-trained young adults.

The objective of the current study was to compare the effects of resistance training frequency on cognitive inhibitory control in young adults with previous experience in the modality. Male participants (N = 36) were randomly placed into one of three experimental groups. Participants performed resistance training 1 (F1), 2 (F2), and 3 (F3) times per week for 24 weeks. The three groups performed exercises of equal intensity, volume-load, and rest duration. Cognitive inhibitory control (via Stroop test) was tested 72 h before (pre-experiment) and 72 h after (post-experiment) the resistance training program. No time vs. group interaction effects were noted for accuracy (F(4, 29) = 3.57, p = 0.18) or response time (F(4, 29) = 2.61, p = 0.06) on the Stroop test. These results indicate that increased resistance training frequency, when volume-load is kept constant, does not appear to potentiate cognitive inhibitory control.

Effect of Resistance Training Frequency on Gains in Muscular Strength: A Systematic Review and Meta-Analysis.

Current recommendations on resistance training (RT) frequency for gains in muscular strength are based on extrapolations from limited evidence on the topic, and thus their practical applicability remains questionable. To elucidate this issue, we conducted a systematic review and meta-analysis of the studies that compared muscular strength outcomes with different RT frequencies. To carry out this review, English-language literature searches of the PubMed/MEDLINE, Scopus, and SPORTDiscus databases were conducted. The meta-analysis was performed using a random-effects model. The meta-analysis models were generated with RT frequencies classified as a categorical variable as either 1, 2, 3, or 4+ times/week, or, if there were insufficient data in subgroup analyses, the training frequencies were categorized as 1, 2, or 3 times/week. Subgroup analyses were performed for potential moderators, including (1) training volume; (2) exercise selection for the 1 repetition maximum (RM) test (for both multi-joint and single-joint exercises); (3) upper and lower body strength gains; (4) training to muscular failure (for studies involving and not involving training to muscular failure); (5) age (for both middle-aged/older adults and young adults); and (6) sex (for men and for women). The methodological quality of studies was appraised using the modified Downs and Black checklist. A total of 22 studies were found to meet the inclusion criteria. The average score on the Downs and Black checklist was 18 (range 13-22 points). Four studies were classified as being of good methodological quality, while the rest were classified as being of moderate methodological quality. Results of the meta-analysis showed a significant effect (p=0.003) of RT frequency on muscular strength gains. Effect sizes increased in magnitude from 0.74, 0.82, 0.93, and 1.08 for training 1, 2, 3, and 4+ times per week, respectively. A subgroup analysis of volume-equated studies showed no significant effect (p=0.421) of RT frequency on muscular strength gains. The subgroup analysis for exercise selection for the 1RM test suggested a significant effect of RT frequency on multi-joint (p<0.001), but not single-joint, 1RM test results (p=0.324). The subgroup analysis for upper and lower body showed a significant effect of frequency (p=0.004) for upper body, but not lower body, strength gains (p=0.070). In the subgroup analysis for studies in which the training was and was not carried out to muscular failure, no significant effect of RT frequency was found. The subgroup analysis for the age groups suggested a significant effect of training frequency among young adults (p=0.024), but not among middle-aged and older adults (p=0.093). Finally, the subgroup analysis for sex indicated a significant effect of RT frequency on strength gains in women (p=0.030), but not men (p=0.190). The results of the present systematic review and meta-analysis suggest a significant effect of RT frequency as higher training frequencies are translated into greater muscular strength gains. However, these effects seem to be primarily driven by training volume because when the volume is equated, there was no significant effect of RT frequency on muscular strength gains. Thus, from a practical standpoint, greater training frequencies can be used for additional RT volume, which is then likely to result in greater muscular strength gains. However, it remains unclear whether RT frequency on its own has significant effects on strength gain. It seems that higher RT frequencies result in greater gains in muscular strength on multi-joint exercises in the upper body and in women, and, finally, in contrast to older adults, young individuals seem to respond more positively to greater RT frequencies. More evidence among resistance-trained individuals is needed as most of the current studies were performed in untrained participants.

Effects of resistance training frequency on cardiorespiratory fitness in older men and women during intervention and follow-up

This study investigated the effects of resistance training (RT) performed with different frequencies, including a follow-up period, on cardiorespiratory fitness in healthy older individuals. Eighty-eight men and women (69±3years, 167±9cm and 78±14kg) were randomly placed into four groups: training one- (M1=11, W1=12), two- (M2=7, W2=14), or three- (M3=11, W3=13) times-per-week or a non-training control group (MCon=11, WCon=9). During months 1–3, all subjects trained two-times-per-week while during the subsequent 6months, training frequency was set according to the group. Oxygen consumption (cycling economy: CE), gross efficiency (GE), blood lactate concentrations (La) and heart rate (HR) were evaluated during a submaximal cycle ergometer test. Hemoglobin (Hb), hematocrit (Hct), heart rate (HRrest) and body composition by DXA were also measured at rest. Maximal strength was measured by a 1-RM leg press test. Most improvements in CE, GE, La and HR occurred in all groups during months 1–3. No additional statistically significant improvements were observed during months 4–9, although effect sizes for the change in CE and GE at higher workloads indicated a dose-response pattern in men (CE at 75W: M1 g=0.13, M2 g=−0.58, M3 g=−0.89; 100W: M1 g=0.43, M2 g=−0.59, M3 g=−0.68) i.e. higher training frequency (two- and three-times-per-week versus one-time-per-week) led to greater improvements once the typical plateau in performance had occurred. Hb increased in W1 and W2, while no changes were observed in Hct or HRrest. 1-RM increased from months 1–3 in all intervention groups (except M2) and from month 4–9 only in M3 and in all women intervention groups. During follow-up, maximal strength was maintained but cycling economy returned to the baseline values in all training groups. These data indicate that RT led to significant improvements in cardiorespiratory fitness during the initial 3months of training. This was partly explained by the RT protocol performed but further improvements may require higher training frequency. These changes are likely to be originated by the improved cardiorespiratory functions rather than neuromuscular adaptations evidenced by a lack of significant relationship during the intervention as well as the divergent results during follow-up.

Effects of Resistance Training Frequency on Short-Term Neuromuscular Adaptations in Untrained Participants

Objective: The purpose of this study was to evaluate whether performing resistance training four days per week was superior to two days per week, in promoting strength and neuromuscular adaptations of the leg extensor muscles. Methods: Nine untrained participants (21.4 ± 2.0 years) were pair matched according to gender and leg extensor maximal voluntary contraction (MVC) and randomly assigned to either a low frequency group (LFG) or a high frequency group (HFG). MVC, 10-repetition maximum (10 RM), and voluntary muscle activation (VA) were recorded pre and post two weeks of unilateral leg extension resistance training. The interpolated twitch technique was used to estimate VA and surface electromyography data was recorded during MVC. Results: VA and 10 RM increased significantly for both groups. For LFG, VA increased from 84.5% ± 5.0% to 92.5% ± 3.4% (p = 0.003) and for HFG, VA increased from 87.3% ± 2.1% to 95.3% ± 1.3% (p = 0.006). 10 RM increased from 43.2 ± 8.0 kg to 48.2 ± 6.2 kg (p = 0.034) and from 45.3 ± 5.9 to 49.0 ± 7.4 kg (p = 0.05) for LFG and HFG, respectively. No differences were observed between groups. Thus, two weeks of resistance training significantly increased the 10 RM and VA in both groups, while no differences were observed between groups. Conclusions: These results indicate that performing resistance training two or four times per week are equally effective in promoting strength and neuromuscular adaptations, when weekly volume is equalized.

Effects of Resistance Training Frequency on Measures of Muscle Hypertrophy: A Systematic Review and Meta-Analysis.

A number of resistance training (RT) program variables can be manipulated to maximize muscular hypertrophy. One variable of primary interest in this regard is RT frequency. Frequency can refer to the number of resistance training sessions performed in a given period of time, as well as to the number of times a specific muscle group is trained over a given period of time. We conducted a systematic review and meta-analysis to determine the effects of resistance training frequency on hypertrophic outcomes. Studies were deemed eligible for inclusion if they met the following criteria: (1) were an experimental trial published in an English-language refereed journal; (2) directly compared different weekly resistance training frequencies in traditional dynamic exercise using coupled concentric and eccentric actions; (3) measured morphologic changes via biopsy, imaging, circumference, and/or densitometry; (4) had a minimum duration of 4weeks; and (5) used human participants without chronic disease or injury. A total of ten studies were identified that investigated RT frequency in accordance with the criteria outlined. Analysis using binary frequency as a predictor variable revealed a significant impact of training frequency on hypertrophy effect size (P=0.002), with higher frequency being associated with a greater effect size than lower frequency (0.49±0.08 vs. 0.30±0.07, respectively). Statistical analyses of studies investigating training session frequency when groups are matched for frequency of training per muscle group could not be carried out and reliable estimates could not be generated due to inadequate sample size. When comparing studies that investigated training muscle groups between 1 to 3days per week on a volume-equated basis, the current body of evidence indicates that frequencies of training twice a week promote superior hypertrophic outcomes to once a week. It can therefore be inferred that the major muscle groups should be trained at least twice a week to maximize muscle growth; whether training a muscle group three times per week is superior to a twice-per-week protocol remains to be determined.

Effect of resistance training frequency on physiological adaptations in older adults

Resistance training is an effective way to achieve optimal gains in muscle mass and strength and has also been well documented in attenuating various forms of skeletal muscle wasting (e.g., sarcopenia). Moreover, it has been demonstrated that with appropriate training, older adults can reverse strength and muscle mass deficits to younger levels. To attain maximal benefits, careful manipulation of training variables, such as intensity, volume and frequency, is required. Although training intensity and training volume have been extensively studied, there is only scarce information available on the adaptive responses to frequency manipulations in older populations. Thus, we compared the effects of short-term (8 weeks) resistance training programs performed either 2 days/week (n = 15, 7 males, 8 females) or 3 days/week (n = 14, 4 males, 10 females) on muscle mass, upper- and lower-body strength and functional abilities in individuals aged > 60 years. Chest press strength increased in both the 2 times/week and 3 times/week groups over the 8-week training period by 20.84% and 20.18%, respectively. Lower-body (leg press) strength also showed improvements in both groups: 22.34% in the 2 times/week group and 28.12% in the 3 times/week group. There was a slight, but nevertheless significant gain of lean body mass from pre- to post-training (2.4% and 1.9% for the 2 days and 3 days groups, respectively). However, functional performance remained unchanged in the groups. We found that short-term resistance training 2 times/week or 3 times/week elicited comparable muscle strength and lean body mass adaptations in older adults.

Does frequency of resistance training affect tibial cortical bone density in older women? A randomized controlled trial

SummaryThis randomized controlled trial evaluated the effect of resistance training frequency (0, 1, and 2 times/week) on cortical volumetric bone mineral density (vBMD) at the tibia in older women. There was no mean difference in change in tibial cortical vBMD in older women who engaged in resistance training (RT) one or two times/week compared with the control group over 12 months after adjusting for baseline values.IntroductionNational guidelines recommend RT two to three times/week to optimize bone health. Our objective was to determine the effect of a 12-month intervention of three different RT frequencies on tibial volumetric cortical density (CovBMD) in healthy older women.MethodsWe randomized participants to the following groups: (1) 2×/week balance and tone group (i.e., no resistance beyond body weight, BT), (2) 1×/week RT (RT1), and (3) 2×/week RT (RT2). Treatment allocation was concealed, and measurement team and the bone data analyst were blinded to group allocation. We used peripheral quantitative computed tomography to acquire one 2.3-mm scan at the 50 % tibia, and the primary outcome was CovBMD. Data were collected at baseline, 6 and 12 months, and we used linear mixed modeling to assess the effect at 12 months.ResultsWe assessed 147 participants; 100 women provided data at all three points. Baseline unadjusted mean (SD) tibial CovBMD (in milligrams per cubic centimeter) at the 50 % site was 1,077.4 (43.0) (BT), 1,087.8 (42.0) (RT1), and 1,058.7 (60.4) (RT2). At 12 months, there were no statistically significant differences (−0.45 to −0.17 %) between BT and RT groups for mean difference in change in tibial CovBMD for exercise interventions (BT, RT1, RT2) after adjusting for baseline tibial CovBMD.ConclusionWe note no mean difference in change in tibial CovBMD in older women who engaged in RT one or two times/week compared with the control group over 12 months. It is unknown if RT of 3× or 4×/week would be enough to promote a statistically significant difference in change of bone density.

Short-Term Effects of Resistance Training Frequency on Body Composition and Strength in Middle-Aged Women

Although a dose-response relationship between resistance training frequency and strength has been identified, there is limited research regarding the association between frequency and body composition. This study evaluated the effects of 3 vs. 4 d·wk(-1) of resistance training on body composition and strength in middle-aged women. Twenty-one untrained women (age 47.6 ± 1.2 years) completed 8 weeks of resistance training either 3 nonconsecutive days of the week using a traditional total-body protocol (RT3) or 4 consecutive days of the week using an alternating split-training protocol (RT4). The RT3 completed 3 sets of 8 exercises, whereas RT4 completed 3 sets of 6 upper body exercises or 6 sets of 3 lower body exercises. Both groups completed 72 sets per week of 8-12 repetitions at 50-80% 1 repetition maximum. Weekly training volume load was calculated as the total number of repetitions × load (kg) completed per week. Body composition was measured using air displacement plethysmography. At baseline and after 8 weeks of resistance training, there were no significant between-group differences. Both protocols resulted in significant increases in absolute lean mass (1.1 ± 0.3 kg; p = 0.001), body weight (1.02 ± 0.3 kg; p = 0.005), body mass index (0.3 ± 0.1 kg·m(-2); p = 0.006), strength (p < 0.001), and weekly training volume load (p < 0.001). Correlation analysis revealed that weekly training volume load was strongly and positively related to gains in lean mass (r = 0.56, p = 0.05) and strength (r = 0.60, p = 0.006). In these untrained, middle-aged women, initial short-term gains in lean mass and strength were not influenced by training frequency when the number of training sets per week was equated.

Effect of Resistance Training Frequency on Functional Flexibility in Middle-Aged Women

Even though age results in decreased flexibility, the effect of resistance training (RT) frequency on functional flexibility in middle-aged women has not been well studied. PURPOSE: This study evaluated the effects of a 3 versus 4 day RT program on changes in flexibility of the arms of the dominant and non-dominant hand as well as the lower body. METHODS: Twenty-one untrained women (age 48±1.2 years; BMI 28.9±1.1) completed 8 weeks of RT. Self-selected groups enhanced adherence to training in group 3 (G3) or group 4 (G4). G3 trained total body 3 days a week and G4 trained 4 consecutive days alternating upper and lower body exercises. G4 completed 3 sets of 6 upper body exercises (chest press, latissimus pulldown, shoulder press, machine row, triceps pushdown, biceps curl) or 6 sets of 3 lower body exercises (leg press, leg extension, leg curl). G3 completed 3 sets of the same exercises (excluding machine row) used for split training by G4. Both groups completed 72 sets of 8-12 repetitions at 50-80% 1RM per week. A control group of 7 untrained women (age 50±6.5 years; BMI 31.9±7.2) completed no exercise but only pre-post flexibility testing. Flexibility was measured using a modified Apley's Scratch test. Participants reached over and behind the head with the dominant hand and behind the back and up with the non-dominant hand. This was repeated in reverse and scores where measured based on the centimeters their hands failed to touch by (- scores) or by an overlap of their fingers (+ scores). Lower body flexibility was measured using an electronic flexometer in centimeters. RESULTS: Both RT protocols were well tolerated with 98% adherence that resulted in significant increases in upper and lower body strength (p <.01). There were no significant between group differences on the three measures of flexibility from pre to post testing. However, a small non-significant increase in flexibility in the non-dominant arm and lower body did occur in the exercise groups. Non-dominant arm flexibility increased.58 cm, and lower body flexibility increased 2.3 cm. CONCLUSIONS: Strength training in middle-aged women 3 or 4 days a week following ACSM guidelines will not alter functional flexibility. It is safe for middle aged women to perform strength training programs and not fear the development of muscle bound physiques or losing functional flexibility.

Effect Of Resistance Training Frequency On Body Composition In Middle-aged Women

The effect of resistance training (RT) frequency on body composition has not been well studied in women, although they are at high risk for loss of lean mass with age. PURPOSE: This study evaluated short-term effects of a 3- versus 4-day a week RT program on changes in absolute (kg) and relative (%) lean and fat mass. METHODS: Nineteen untrained women (age 48 ± 1.2 years; BMI 28.8 ± 1.2) completed 8 weeks of RT. To promote adherence they self-selected assignment to either Group 3, which trained 3 nonconsecutive days of the week using a traditional total body protocol, or Group 4, which trained 4 consecutive days of the week using an alternating split training (upper-lower body) protocol. Group 4 completed 3 sets of 6 upper body exercises (chest press, latissimus pulldown, shoulder press, machine row, triceps pushdown, biceps curl) or 6 sets of 3 lower body exercises (leg press, leg extension, leg curl). Group 3 completed 3 sets of the same 8 exercises (excluding machine row) used for split training. Both groups completed 72 sets of 8-12 repetitions at 50-80% 1RM per week. Body composition was measured using air displacement plethysmography prior to and after completion of the RT program. To control for diet, participants were instructed not to change their intake or restrict calories during the study. RESULTS: Both RT protocols were well-tolerated, had 98% adherence, and resulted in significant increases in upper and lower body strength (p < 0.01). At baseline and after 8 weeks of RT there were no significant between-group differences in age, body mass, BMI, lean or fat mass. However, when both groups were combined there was a significant increase in absolute lean mass (1.1 ± 0.3 kg; p = 0.002) accompanied by increases in body mass (1.04 ± 0.4 kg; p = 0.009) and BMI (0.38 ± 0.1; p = 0.01). A small, non-significant decrease in % body fat (-0.4 ± 0.3 %) was observed. CONCLUSIONS: In untrained, middle-aged women initial, short-term gains in lean mass are not influenced by a training frequency of either 3 or 4 days a week. Consecutive-day split training is as well tolerated as traditional every-other-day total body training, even by novices. Therefore, for convenience and to promote adherence, women beginning a RT program should be taught both training protocols so they may schedule training sessions to fit their normal, weekly routine as closely as possible.