Review Article

Putative Factors That May Modulate the Effect of Exercise on Liver Fat: Insights from Animal Studies

Table 1

Effect of aerobic exercise training on liver fat in animals.

Withdrawal beforeEffect of training (EX versus
StudyAnimalsInterventionmeasurementsrespective SED group on the same diet)
DietExerciseDurationFoodExerciseBW/VATLiver fat

Ahrens et al., 1972 [12]Male Wistar rats; young and mature HF (ad libitum or pair-fed) with two different carbohydrate sources SED or EX (1/d, running, 30 min at ~13 m/min and 0% incline)8 wk12 h?/? (both diets, feeding patterns, and age groups)Young: −15%
Mature: −35%

Barakat et al., 1987 [13]Female rats; control and alloxan-diabeticSC? (ad libitum)SED or EX (1/d, running, 2 h at 20 m/min and 0% incline)7 d0 h24 h/? (both groups)Control: −14% (NS)
Diabetic: −2% (NS)

Cha et al., 1999 [14]Male Sprague-Dawley ratsSC or HF (ad libitum)SED or EX (1/d, running, 1.5 h at 150 m/min and 1% incline)1 mo??SC: /?
HF: /?
SC: −24%
HF: −40%

Chapados et al., 2009 [15]Female Sprague-Dawley ratsSC or HF (ad libitum)SED or EX (5/wk, running, progressive until 1 h at 26 m/min and 10% incline for the last 4 wk)8 wk12 h48 hSC: /
HF: /
SC: −16% (NS)
HF: −22% (NS)

Charbonneau et al., 2005 [16]Female Sprague-Dawley ratsSC or HF (ad libitum)SED or EX (6/wk, running, progressive until 1 h at 26 m/min and 10% incline for the last 3 wk)6 wk (+2 wk diet lead-in)2-3 h48 hSC: /
HF: /
SC: 0% (NS)
HF: −14%

Fukuda et al., 1991 [17]Male Wistar ratsSC, HF or HChol (ad libitum)SED or EX (voluntary running)4 wk3 h?SC: /?
HF: /?
HChol: /?
SC: −1% (NS)
HF: +14% (NS)
HChol: −30% (NS)

Gauthier et al., 2003 [18]Female Sprague-Dawley ratsSC or HF (ad libitum)SED or EX (5/wk, running, progressive until 1 h at 26 m/min and 10% incline for the last 4 wk)8 wk2 h48 hSC: /
HF: /↓↓
SC: +16% (NS)
HF: −29%

Gauthier et al., 2004 [19]Female Sprague-Dawley ratsHF (ad libitum)SED or EX (5/wk, running, progressive until 1 h at 26 m/min and 10% incline for the last 4 wk)8 wk (+8 wk diet lead-in)2 h48 h/−16% (NS)

Gollisch et al., 2009 [20]Female Sprague-Dawley ratsSC or HF (ad libitum)SED or EX (voluntary running)4 wk10 h24 hSC: /
HF: /↓↓
SC: −16% (NS)
HF: −31%
Hao et al., 2010 [21]Female Sprague-Dawley rats; sham-operated or OVX with and without E2SC (ad libitum) SED or EX (5/wk, running, 1 h at 18 m/min and 0% incline)12 wk?24 hSham: /
OVX: /
OVX+E2: /
Sham: −24%
OVX: −30%
OVX+E2: −5% (NS)

Karanth and Jeevaratnam, 2009 [22]Male Wistar ratsHF rich in SFA or MUFA (ad libitum) with carnitine or notSED or EX (6/wk, swimming, 1 h)6 moOvernight20 h/? (both diets)SFA: −35%
MUFA: −25%
(average with or without carnitine)

Lessard et al., 2007 [23]Male Sprague-Dawley ratsHF (ad libitum)SED or EX (5/wk, running, progressive until 1 h at 32 m/min and 15% incline for the last 3 wk)4 wk (+4 wk diet lead-in)8–12 h36–48 h/−41%

Lira et al., 2008 [24]Male Wistar rats; control and tumor-bearingSC (ad libitum)SED or EX (5/wk, running, progressive until 1 h at 20 m/min and 0% incline for the last 2 wk)8 wk?24 h/? (both groups)Control: −30%
Tumor: −92%

Morifuji et al., 2006 [25]Male Sprague-Dawley ratsSC with casein or soya as protein source (ad libitum)SED or EX (6/wk, swimming, 2 h)2 wkNonfasting24 h/ (both groups)Casein: −21%
Soya: −24%

Narayan et al., 1975 [26]Male Holtzman ratsSC or HF (ad libitum)SED or EX (5/wk, running, progressive until 80–85 min at 23 m/min and 8.5% incline for the last 3 wk)6 wkNonfasting24 h?/?SC: +81% (NS)
HF: −51%

Petridou et al., 2005 [27]Male Wistar ratsSC (ad libitum)SED or EX (voluntary running)8 wk6 h12 h?/?−12% (NS)

Pighon et al., 2010 [28]Female Sprague-Dawley ratsSC (ad libitum)SED or EX (5/wk, running, progressive until 1 h min at 26 m/min and 10% incline for the last 4 wk)6 wk3 h48 h/+1% (NS)

Pighon et al., 2010 [28]Female Sprague-Dawley rats; sham-operated or OVX with and without E2SC (ad libitum)SED or EX (5/wk, running, progressive until 1 h min at 26 m/min and 10% incline for the last 3 wk)5 wk3 h48 h/ (all groups)Sham: −1% (NS)
OVX: −26%
OVX+E2: −5% (NS)
Rector et al., 2008 [29] Male OLETF rats (obese and diabetic)SC (ad libitum) SED or EX (voluntary running)16 wk5 h48 h/−45%
Rothfeld et al., 1977 [30]Male Sprague-Dawley ratsHF (pair-fed)SED or EX (voluntary running)3 wk???/?−14%

Straczkowski et al., 2001 [31]Male Wistar ratsSC for wk 0–3 and SC or HF for wk 4–6 (pair-fed)SED or EX (6/wk, running, 3 h at 20 m/min and 10% incline)6 wk?48 h/? (both diets)SC: +97%
HF: −9% (NS)

Terao et al., 1987 [32]Male Wistar ratsHChol (ad libitum)SED or EX (5/wk, running, progressive until 1 h at 20 m/min and 0% incline for the last 2 wk)5 wk (+5 wk SC diet lead-in)??/?−16% (NS)

Tsutsumi et al., 2001 [33]Male Sprague-Dawley old ratsSC (ad libitum)SED or EX (1/d, running, 30 min at 15 m/min and 10% incline)3 mo~12 h~12 h/−41%

Vieira et al., 2009 [34]Male C57BL/6, HF diet-induced obese miceSC or HF (ad libitum)SED or EX (5/wk, running, 40 min at 12 m/min and 12% incline)6 wk12 h48 hSC: /
HF: /
SC: −49% (NS)
HF: −11% (NS)

Vieira et al., 2009 [34]Male C57BL/6, HF diet-induced obese miceSC or HF (ad libitum)SED or EX (5/wk, running, 40 min at 12 m/min and 12% incline)12 wk12 h48 hSC: /
HF: /
SC: −72%
HF: −48%

Vieira et al., 2009 [35]Male Balb/cByJ mice (with defective fatty acid oxidation)SC or HF (ad libitum)SED or EX (5/wk, running, 1 h at 12 m/min and 5% incline)12 wk12 h48 hSC: /?
HF: /?
SC: −5% (NS)
HF: −40% ( 𝑃 = 0 . 0 9 )

Yasari et al., 2006 [36]Female Sprague-Dawley ratsSC (ad libitum)SED or EX (5/wk, running, progressive until 1 h at 26 m/min and 10% incline for the last 4 wk)8 wk3 h48 h/−9% (NS)

Yasari et al., 2010 [37]Female Sprague-Dawley ratsSC for wk 0–6 and SC or HF for wk 7-8 (ad libitum)SED or EX (5/wk, running, progressive until 1 h at 26 m/min and 10% incline for the last 4 wk)8 wk3 h36–48 h/ (both diets)SC: −13% (NS)
HF: +7% (NS)

All changes shown are statistically significant versus control group (SED), unless indicated otherwise ( is unchanged; is reduced; NS is not significant; ? is unknown).
BW: body weight; E2: estradiol; EX: exercised; HChol: high fat and cholesterol; HF: high fat; MUFA: monounsaturated fatty acids; OVX: ovariectomized; SC: standard chow (low fat); SED: sedentary; SFA: saturated fatty acids; VAT: visceral adipose tissue (mesenteric, retroperitoneal, and/or epididymal fat pads).