Weekly Training Frequency Effects on Strength Gain: A Meta-Analysis

Ralston, Grant W.; Kilgore, Lon; Wyatt, Frank B.; Buchan, Duncan; Baker, Julien S.

doi:10.1186/s40798-018-0149-9

Sports Medicine - Open

Table 3 Excluded studies from meta-analysis due to confounding factors

From: Weekly Training Frequency Effects on Strength Gain: A Meta-Analysis

Study	N	Age, years (mean ± SD)	Duration	Testing modality	Sets (reps)	Days trained per week	Frequency per week	Pre- vs. post-intervention kg, mean ± SD	Pre- vs. post-intervention strength difference kg (% change)	p value (pre vs. post)	ES
Gomes et al. [20]	12 11	25.5 (± 1.25) 27.1 (± 1.85)	8 weeks	Sq	5–10 (8–12)	1 5	LF HF	132.9 ± 28.0 vs. 140.9 ± 25.5 123.3 ± 17.5 vs. 135.3 ± 22.2	8 (6.02) 12 (9.73)	0.47 0.17	0.30 0.60
Gomes et al. [20]	12 11	25.5 (± 1.25) 27.1 (± 1.85)	8 weeks	BP	5–10 (8–12)	1 5	LF HF	103.5 ± 15.4 vs. 109.1 ± 18.5 100.6 ± 14.5 vs. 110.3 ± 12.1	5.6 (5.41) 9.7 (9.64)	0.43 0.10	0.33 0.73
Serra et al. [21]	26 32 16	35.3 (± 1.75) 34 (± 2) 34.85 (± 0.85)	3 months	WG PullD	3 (10–20)	2 3 4	MF HF HF	42.6 ± 20.7 vs. 48.5 ± 20.7 44.4 ± 13.9 vs. 51.3 ± 13.9 40.6 ± 20.3 vs. 48.6 ± 21.8	5.9 (13.8) 6.9 (13.5) 8 (16.5)	≤ 0.001 ^a ≤ 0.001^a ≤ 0.001^a	0.29 0.50 0.38
Serra et al. [21]	26 32 16	35.3 (± 1.75) 34 (± 2) 34.85 (± 0.85)	3 months	CP	3 (10–20)	2 3 4	MF HF^e HF	41.2 ± 25.6 vs. 49.9 ± 30.2 46.6 ± 20.8 vs. 59.7 ± 25.1 42.1 ± 27.9 vs. 55.6 ± 36.2	8.7 (21.1) 13.1 (28.1) 13.5 (32.1)	≤ 0.001^a ≤ 0.001^a ≤ 0.00^a	0.31 0.57 0.42
Serra et al. [21]	26 32 16	35.3 (± 1.75) 34 (± 2) 34.85 (± 0.85)	3 months	LP	3 (10–20)	2 3 4	MF HF^e HF	108.9 ± 49.1 vs. 128.9 ± 54.5 120.2 ± 48.0 vs. 149.0 ± 57.7 128.8 ± 55.4 vs. 168.1 ± 89.0	20 (18.4) 28.8 (24.0) 39.3 (30.5)	≤ 0.001^a ≤ 0.001^a ≤ 0.001^a	0.39 0.54 0.53
Yue et al. [23]	9 9	28 (± 7.9) 21 (± 3.2)	6 weeks	Sq	4 (8–12) 2 (8–12)	2 4	MF HF	103 ± 27 vs. 115 ± 34 90 ± 9 vs. 103 ± 13	12 (11.7) 13 (14.4)	≤ 0.001^a ≤ 0.001^a	0.39 1.16
Yue et al. [23]	9 9	28 (± 7.9) 21 (± 3.2)	6 weeks	BP	4 (8–12) 2 (8–12)	2 4	MF HF	77 ± 27 vs. 88 ± 30 70 ± 17 vs. 81 ± 15	11 (14.3) 11 (15.7)	≤ 0.001^a ≤ 0.001^a	0.39 0.69
Carpenter et al. [34]	10 12 12 7	31(± 31)	20 weeks	LumExt	1 (8–12)	0.5 2 3 4	LF MF HF HF	73.6 ± 24.7 vs. 98.2 ± 32.8 58.9 ± 18.0 vs. 86.2 ± 28.0 69.9 ± 27.5 vs. 105.9 ± 40.8 78.2 ± 21.4 vs. 115.8 ± 31.3	24.6 (33.4) 27.3 (46.3) 36 (51.5) 37.6 (48.1)	≤ 0.05^b ≤ 0.05^b ≤ 0.05^b ≤ 0.05^b	0.85 1.16 1.03 1.40
Pollock et al. [35]	14 19	26 (± 9) 30 (± 9)	12 weeks	CervExt	1 (8–12)	1 2	LF MF	28.3 ± 6.7 vs. 38.2 ± 7.8 27.4 ± 8.5 vs. 38.2 ± 10.9	9.9 (35.0) 10.8 (40.9)	0.001^a 0.002^b	1.36 1.10
Taaffe et al. [40]	11 12 11	68.5 (± 3.6) 69.4 (± 3.0) 71.0 (± 4.1)	24 weeks	LPull	3 (8)	1 2 3	LF MF HF	36.0 ± 14.2 vs. 45.3 ± 4.31 35.8 ± 9.7 vs. 47.0 ± 4.20 33.6 ± 10.9 vs. 48.9 ± 4.31	9.3 (25.83) 11.2 (31.28) 15.3 (45.54)	≤ 0.001^a ≤ 0.001^a ≤ 0.001^a	0.89 1.50 1.85
Taaffe et al. [40]	11 12 11	68.5 (± 3.6) 69.4 (± 3.0) 71.0 (± 4.1)	24 weeks	BC	3 (8)	1 2 3	LF MF HF	16.5 ± 7.1 vs. 21.9 ± 2.99 17.0 ± 4.3 vs. 24.4 ± 2.77 16.7 ± 6.2 vs. 23.2 ± 2.99	5.4 (32.73) 7.4 (43.53) 6.5 (38.92)	≤ 0.001^a ≤ 0.001^a ≤ 0.001^a	0.99 2.05 1.34
Taaffe et al. [40]	11 12 11	68.5 (± 3.6) 69.4 (± 3.0) 71.0 (± 4.1)	24 weeks	BExt	3 (8)	1 2 3	LF MF HF	62.3 ± 24.5 vs. 83.1 ± 9.17 63.4 ± 11.3 vs. 84.2 ± 9.70 65.0 ± 26.5 vs. 84.4 ± 9.29	20.8 (33.39) 20.8 (32.81) 19.4 (29.85)	≤ 0.001^a ≤ 0.001^a ≤ 0.001^a	1.12 1.98 0.98
Taaffe et al. [40]	11 12 11	68.5 (± 3.6) 69.4 (± 3.0) 71.0 (± 4.1)	24 weeks	LP	3 (8)	1 2 3	LF MF HF	109.5 ± 29.8 vs. 135.2 ± 12.27 113.3 ± 19.3 vs. 142.8 ± 12.47 110.5 ± 29.5 vs. 145.1 ± 3.7	25.7 (23.47) 29.5 (26.04) 34.6 (31.31)	≤ 0.001^a ≤ 0.001^a ≤ 0.001^a	1.13 1.82 1.65
Taaffe et al. [40]	11 12 11	68.5 (± 3.6) 69.4 (± 3.0) 71.0 (± 4.1)	24 weeks	KExt	3 (8)	1 2 3	LF MF HF	39.3 ± 15.4 vs. 67.1 ± 10.95 43.2 ± 8.6 vs. 72.6 ± 10.74 42.4 ± 12.4 vs. 62.6 ± 10.61	27.8 (70.74) 29.4 (68.06) 20.2 (47.64)	≤ 0.001^a ≤ 0.001^a ≤ 0.001^a	2.08 3.02 1.75
Taaffe et al. [40]	10 12 11	68.5 (± 3.6) 69.4 (± 3.0) 71.0 (± 4.1)	24 weeks	KFlex	3 (8)	1 2 3	LF MF HF	16.3 ± 7.5 vs. 28.4 ± 4.43 19.6 ± 6.8 vs. 30.4 ± 4.50 20.0 ± 9.4 vs. 28.5 ± 4.64	12.1 (74.23) 10.8 (55.10) 8.5 (42.50)	≤ 0.001^a ≤ 0.001^a ≤ 0.001^a	1.96 1.87 1.15
Farinatti et al. [41]	10 11 10	72 (± 5.0) 66 (± 7.0) 68 (± 4.0)	16 weeks	DumBP	1 (8–12)	1 2 3	LF MF HF	8.2 ± 1.8 vs. 13.0 ± 2.0 9.6 ± 2.2 vs. 14.4 ± 5.2 10.4 ± 0.9 vs. 15.6 ± 1.7	4.8 (58.54) 4.8 (50.0) 5.2 (50.0)	≤ 0.01^a ≤ 0.01^a ≤ 0.01^a	2.52 1.20 3.82
Farinatti et al. [41]	10 11 10	72 (± 5.0) 66 (± 7.0) 68 (± 4.0)	16 weeks	DCur	1 (8–12)	1 2 3	LF MF HF	7.8 ± 1.5 vs. 12.2 ± 2.3 8.4 ± 1.7 vs. 13.6 ± 2.6 9.2 ± 1.8 vs. 15.6 ± 0.9	4.4 (56.41) 5.2 (61.90) 6.4 (69.57)	≤ 0.01^a ≤ 0.01^a ≤ 0.01^a	2.27 2.37 4.50
Farinatti et al. [41]	10 11 10	72 (± 5.0) 66 (± 7.0) 68 (± 4.0)	16 weeks	KExt	1 (8–12)	1 2 3	LF MF HF	18.0 ± 3.7 vs. 25.6 ± 3.2 19.2 ± 4.6 ± 29.6 ± 7.4 19.8 ± 4.9 vs. 32.0 ± 6.8	7.6 (42.22) 10.4 (54.17) 12.2 (61.62)	≤ 0.01^a ≤ 0.01^a ≤ 0.01^a	2.20 1.69 2.06
Farinatti et al. [42]	10 11 10	72 (± 5.0) 66 (± 7.0) 68 (± 4.0)	16 weeks	StCR	1 (8–12)	1 2 3	LF MF HF	12.0 ± 2.0 vs. 16.8 ± 1.9 12.2 ± 3.0 vs. 17.0 ± 3.7 11.8 ± 0.5 vs. 16.8 ± 1.5	4.8 (40.0) 4.8 (39.34) 5.0 (42.37)	≤ 0.01^a ≤ 0.01^a ≤ 0.01^a	2.46 1.43 4.47
Burt et al. [42]	10 11	Students	8 weeks.	LP	1 (6–10)	1 2	LF MF	263.31 ± 37.23 vs. 362.65 ± 51.06 244.89 ± 45.80 vs. 391.53 ± 45.18	99.34 (99.34) 146.64 (59.9)	≤ 0.0001^a ≤ 0.0001^a	2.22 3.22
Serra et al. [67]	18 17 10	41.4 (± 9.9)	4 months 8 months	BP	3 (10–12)	2 3 4	MF HF HF	41.7 ± 16.4 vs. 57.4 ± 15.4 38.8 ± 16.3 vs. 59.5 ± 16.5 39.0 ± 16.1 vs. 62.8 ± 18.1	36.3 (37.6) 46.5 (53.4) 65.1 (61.0)	0.01^a 0.001^a 0.01^a	0.99 1.26 1.39
Serra et al. [67]	18 17 10	41.4 (± 9.9)	4 months 8 months	LP	3 (10–12)	2 3 4	MF HF HF	83.3 ± 21.4 vs. 113.3 ± 26.6 88.2 ± 21.9 vs. 112.5 ± 18.5 80.0 ± 25.4 vs. 117.8 ± 30.5	30.4 (36.01) 32.4 (27.6) 45.4 (47.3)	0.001^a ≤ 0.001^a 0.01^a	1.24 1.20 1.35
Serra et al. [67]	18 17 10	41.4 (± 9.9)	4 months 8 months	LPull	3 (10–12)	2 3 4	MF HF HF	50.1 ± 12.0 vs. 67.4 ± 12.0 52.2 ± 12.8 vs. 69.7 ± 17.0 54.5 ± 16.2 vs. 77.5 ± 18.1	29.4 (34.5) 32.0 (33.5) 46.0 (42.2)	0.0001^a 0.002^a 0.01^a	1.44 1.16 1.34
Benton et al. [36]	11 10	47.6 (± 1.2)	8 weeks	CP	3–6 (8–12)	3 4	HF HF	37.4 ± 2.5 vs. 50.0 ± 3.5 44.5 ± 3.0 vs. 59.7 ± 4.1	12.6 (34.0) 15.2 (34.2)	≤ 0.001^a ≤ 0.001^a	1.25 1.34
Benton et al. [36]	11 10	47.6 (± 1.2)	8 weeks	LP	3–6 (8–12)	3 4	HF HF	105.1 ± 9.8 vs. 135.7 ± 16.7 119.7 ± 11.5 vs. 178.6 ± 19.6	30.6 (29.1) 58.9 (49.2)	≤ 0.001^a ≤ 0.001^a	0.67 1.16
Ribeiro et al. [37]	5 5	26.7 (± 2.7)	4 weeks	BP	4 (6–20)	4 6	HF HF	104.4 ± 19.3 vs. 113.2 ± 23.0 105.6 ± 16.4 vs. 117.6 ± 16.3	8.8 (8.4) 12 (11.4)	0.53 0.28	0.41 0.73
Hoffman et al. [38]	12 15 23 11	19.7 ± (1.4) 20.1 ± (1.5) 20.1 ± (1.1) 19.7 ± (1.1)	10 weeks.	BP	1–5 (2–10)	3 4 5 6	HF HF HF HF	107.2 ± 11.6 vs. 109.1 ± 28.7 127.7 ± 13.9 vs. 132.2 ± 14.5 131.1 ± 20.1 vs. 135.3 ± 19.0 143.9 ± 12.0 vs. 149.7 ± 17.3	1.9 (1.8) 4.5 (3.5) 4.2 (3.2) 5.8 (4.0)	0.83 0.39 0.47 0.37	0.09 0.32 0.21 0.39
Hoffman et al. [38]	12 15 23 11	19.7 ± (1.4) 20.1 ± (1.5) 20.1 ± (1.1) 19.7 ± (1.1)	10 weeks.	Sq	1–5 (2–10)	3 4 5 6	HF HF HF HF	140.1 ± 18.6 vs. 147.4 ± 38.9 173.6 ± 36.2 vs. 186.3 ± 31.9 170.6 ± 19.4 vs. 183.4 ± 22.1 191.6 ± 34.9 vs. 204.1 ± 39.5	7.3 (5.2) 12.7 (7.3) 12.8 (7.5) 12.5 (6.5)	0.56 0.32 0.04^a 0.44	0.24 0.37 0.62 0.34
Padilha et al. [43]	13 14	68.9 (± 5.0) 66.7 (± 13.9)	12 weeks	CP	1 (10–15)	2 3	MF HF	35.7 ± 6.6 vs. 42.2 ± 8.0 37.1 ± 3.8 vs. 47.3 ± 4.6	6.5 (18.2) 10.2 (27.5)	≤ 0.05^b ≤ 0.05^b	0.89 2.42
Padilha et al. [43]	13 14	68.9 (± 5.0)	12 weeks	LE	1 (10–15)	2 3	MF HF	41.3 ± 9.3 vs. 48.9 ± 9.1 46.1 ± 10.5 vs. 53.8 ± 12.5	7.6 (18.4) 7.7 (16.7)	≤ 0.05^b ≤ 0.05^b	0.83 0.67
Padilha et al. [43]	13 14	66.7 (± 13.9)	12 weeks	BC	1 (10–15)	2 3	MF HF	17.0 ± 3.3 vs. 23.4 ± 3.8 17.7 ± 2.5 vs. 24.2 ± 3.6	6.4 (37.6) 6.5 (26.9)	≤ 0.05^b ≤ 0.05^b	1.80 2.10
Hunter [39]	14 10	22.2 (± 2.2) ^c	7 weeks	BP	2–3 (7–10)	3 4	HF HF	69.1 ± 22.08 vs. 77.3 ± 20.58 59.3 ± 25.93 vs. 69.20 ± 25.61	8.2 (11.9) 9.9 (16.7)	0.32 0.40	0.38 0.38
Hunter [39]	11 11	23.1 (± 0.9) ^d	7 weeks	BP	2–3 (7–10)	3 4	HF HF	26.1 ± 5.97 vs. 31.3 ± 6.30 27.3 ± 7.30 vs. 36.40 ± 7.96	5.2 (19.9) 9.1 (33.3)	0.32 ≤ 0.05^b	0.85 1.19

Abbreviations: N number of subjects, SD standard deviation, reps repetitions; per week number of days trained per week, ES effect size, Sq squat, LF low frequency (1 day per week), MF medium frequency (2 days per week), HF high frequency (≥ 3 day per week), BP bench press, WGPullD wide grip pulldown, CP chest press, LP leg press, LumExt lumbar extension, CervExt cervical extension, LPull lateral pulldown, BC bicep curl, BExt back extension, LP leg press, KExt knee extension, KFlex knee flexion, DumBP dumbbell bench press, DCurl dumbbell curl, StCR standing calf raise
^aSignificantly greater than prior to training (p ≤ 0.01)
^bSignificantly greater than prior to training (p ≤ 0.05)
^cMale-only subjects
^dFemale-only subjects

Back to article page