. 2021 Nov 4;6(4):93. doi: 10.3390/jfmk6040093

Table 8.

Serum free carnitine (µmol/L) at rest with and without L-carnitine supplementation and serum free carnitine after exercise with and without L-carnitine supplementation.

Authors	Carnitine Dosage		N1	N2	Mean 1	SD 1	Mean 2	SD 2	SMD	SE	95% CI	t	p	Weight (%)		Test for Heterogeneity
														Fixed	Random	Q	72.6140
Arenas 1991 runner	1 g/d, 3 w		13	13	40.0	3	38.0	5	0.470	0.385	−0.326 to 1.265			15.50	9.84	DF	10
Arenas 1991 sprinter	2 g/d, 3 w		11	11	34.0	4	36.0	3	−0.544	0.418	−1.417 to 0.328			13.16	9.70	I² (inconsistency)	86.23%
Arenas 1994	2 g/d, 4 w		7	7	27.8	3.5	31.7	2.9	−1.136	0.544	−2.322 to 0.0504			7.77	9.08	95% CI for I²	77.18 to 91.69
Colombani 1996	4 g/d, 1 d		7	7	41.5	2.9	45.8	2.0	−1.616	0.586	−2.893 to −0.339			6.70	8.86
Cooper 1986	4 g/d, 10 d		10	10	35.4	8.9	33.1	7.9	0.262	0.430	−0.642 to 1.166			12.44	9.64
Gorostiag 1989	2 g/d, 4 w		10	10	31.4	1.7	39.2	3.3	−2.846	0.621	−4.151 to −1.541			5.97	8.67
Marconi 1985	4 g/d, 2 w		6	6	48.0	8.3	56.8	9.6	−0.905	0.564	−2.161 to 0.351			7.24	8.98
Muller 2002	3 g/d, 10 d		10	10	41.10	6.54	52.74	9.23	−1.394	0.482	−2.405 to −0.382			9.92	9.40
Oyono-Enguelle 1989	2 g/d, 3 w		10	10	49.8	2.3	59.4	3.9	−2.872	0.624	−4.183 to −1.560			5.91	8.66
Oyono-Enguelle 1989	2 g/d, 4 w		10	10	49.8	2.3	64.1	3.7	−4.445	0.823	−6.175 to −2.716			3.40	7.57
Oyono-Enguelle 1989	2 g/d, 12 w		10	10	49.8	2.3	48.0	3.5	0.582	0.438	−0.338 to 1.502			12.00	9.61
Total fixed effects			104	104					−0.787	0.152	−1.086 to −0.488	−5.189	<0.001	100.00	100.00
Total random effects			104	104					−1.216	0.416	−2.036 to −0.395	−2.921	0.004	100.00	100.00
Authors	Carn. Dosage	Training	N1	N2	Mean 1	SD 1	Mean 2	SD 2	SMD	SE	95% CI	t	p	Weight (%)		Test for Heterogeneity
														Fixed	Random	Q	24.4106
																DF	6
Arenas 1991 runner	1 g/d, 3 w	After running	13	13	22.9	1.8	25.7	2.6	SMD	SE	95% CI			Weight (%)	SMD	Significance level	p = 0.0004
Arenas 1991 sprinter	2 g/d, 3 w	After running	11	11	18.2	1.5	21.0	1.7	−1.680	0.482	−2.686 to −0.675			Fixed	10.38	I² (inconsistency)	75.42%
Colombani1996	4 g/d, 1 d	After running	7	7	45.8	2.0	70.0	4.9	−1.213	0.415	−2.070 to −0.355			20.37	−1.213	95% CI for I²	48.00 to 88.38
Cooper 1986	4 g/d, 10 d	After 158′ of Marathon	10	10	22.5	2.8	35.0	12.6	−1.680	0.482	−2.686 to −0.675			15.13	−1.680
Gorostiaga1989	2 g/d, 4 w	After 40′ of exercise	10	10	35.5	4.4	38.9	2.8	−6.052	1.248	−8.772 to −3.332			2.26	−6.052
Marconi 1985	4 g/d, 2 w	After 120′ of treadmill	6	6	56.8	9.6	62.5	11.6	−1.312	0.476	−2.311 to −0.312			15.52	−1.312
Nuesch 1999	1 g/d	10′ after maximal treadmill	9	9	71.3	10.2	71.8	10.7	−0.883	0.450	−1.829 to 0.0635			17.32	−0.883
Total (fixed effects)			66	66					−0.494	0.542	−1.702 to 0.714	−5.660	<0.001	11.96	−0.494
Total (random effects)			66	66					−0.0455	0.449	−0.997 to 0.906	−3.253	0.001	17.44	−0.0455
Authors	Carnitine Dosage		N1	N2	Mean 1	SD 1	Mean 2	SD 2	SMD	SE	95% CI	t	p	Weight (%)		Test for Heterogeneity
														Fixed	Random
Arenas 1991 sprinter	2 g/d, 3 w		11	11	34.0	4	36.0	3	−0.544	0.418	−1.417 to 0.328			69.01	51.98	Q	9.5950
Oyono-Enguelle 1989	2 g/d, 3 w		10	10	49.8	2.3	59.4	3.9	−2.872	0.624	−4.183 to −1.560			30.99	48.02	DF	1
Total fixed effects			21	21					−1.266	0.347	−1.968 to −0.563	−3.642	0.001	100.00	100.00	Significance level	p = 0.0020
Total random effects			21	21					−1.662	1.163	−4.012 to 0.688	−1.429	0.161	100.00	100.00	I²	89.58%
																95% CI for I²	61.34 to 97.19
Arenas 1994	2 g/d, 4 w		7	7	27.8	3.5	31.7	2.9	−0.959	0.631	−2.413 to 0.495			41.10	41.10	Q	0.03256
Gorostiaga 1989	2 g/d, 4 w		10	10	31.4	1.7	39.2	3.3	−0.888	0.785	−2.664 to 0.888			26.51	26.51	DF	2
Oyono-Enguelle 1989	2 g/d, 4 w		10	10	49.8	2.3	64.1	3.7	−1.075	0.710	−2.657 to 0.508			32.39	32.39	Significance level	p = 0.9839
Total fixed effects			27	27					−0.978	0.404	−1.801 to −0.154	−2.418	0.021	100.00	100.00	I²	0.00%
Total random effects			27	27					−0.978	0.404	−1.801 to −0.154	−2.418	0.021	100.00	100.00	95% CI for I²	0.00 to 0.00

W: Weeks, g: grams, d: days, l: milliliter, min: minutes, L-carnitine L-carn, SD: standard deviation, N: number of subjects, 1: subjects that did not use carn., 2: subjects used carn, SMD: standard mean differences, SE: standard error, CI: confidential intervals.