Sentences with phrase «fiber type proportion»

We say that muscle fiber type changes either when there is a shift in the isoforms observed in individual fibers (fiber type proportion), or when there is an change in the relative area occupied by each group of fibers.

Most studies indicate that strength training programs of standard durations (6 — 12 weeks) in trained subjects do not lead to a shift between type I to type II muscle fibers, as measured by muscle fiber type proportion, although the effect of longer programs is unknown.

Strength training programs of < 6 months (e.g. Häkkinen et al. 2001; Häkkinen et al. 2003) in trained subjects do not lead to a shift between type I to type II muscle fibers, as measured by muscle fiber type proportion.

On the other hand, there are some indications that strength training programs of < 6 months in untrained subjects can lead to a shift within the sub-types of type II muscle fibers, from type IIX to type IIA muscle fibers, as measured by muscle fiber type proportion.

There are some indications that similar programs can lead to a shift within the sub-types of type II muscle fibers, from type IIX to type IIA muscle fibers, as measured by muscle fiber type proportion.

Not exact matches

• SRK - 015 substantially increases lean body mass in non-human primates, with a particularly notable effect on muscles with a high proportion of fast - twitch fibers, a muscle fiber type that is particularly affected in SMA.

For example, sprinters usually have predominately Type IIB fast glycolytic muscle fibers, while distance runners have a larger proportion of slow - twitch, high oxidative muscle fibers.

In general, endurance athletes tend to display a greater proportion of type I muscle fibers, as shown by early studies (Gollnick et al. 1972; Costill et al. 1979) and later investigations (Harber et al. 2004a).

Nevertheless, it appears that the soleus has a markedly type I fiber proportion, ranging between 70 — 96 %.

Nevertheless, there does appear to be a difference in type IIA and type IIX muscle fiber proportion between strength and power athletes and their respective controls, with most studies reporting a greater proportion of type IIA, and a smaller proportion of type IIX fibers in the athletes (Klitgaard et al. 1990; Jürimäe et al. 1996; Fry et al. 2003a; Fry et al. 2003b; Shoepe et al. 2003; Kesidis et al. 2008) but again this is not seen entirely consistently (D'Antona et al. 2006).

This extremely high proportion of type IIX fibers has not previously been observed.

On the other hand, the gastrocnemius comprises a mixture of type I and type II muscle fibers with a slight tendency towards a greater proportion of type I muscle fibers, with the proportion ranging between 50 — 76 % (Johnson et al. 1973; Edgerton et al. 1975; Dahmane et al. 2005; 2006; Keh - Evans et al. 2010).

Different muscles display different proportions of muscle fiber types.

Strength training in untrained subjects causes a shift in muscle fiber proportion from type IIX to type IIA muscle fiber type, and may also produce similar effects in trained individuals.

Studies to data suggest that strength athletes are likely to display a greater proportion of type II muscle fibers than type I muscle fibers, while non-strength athletes are more likely to display a mixed muscle fiber proportion.

The rectus femoris displays a slight tendency towards a greater proportion of type II muscle fibers, with studies reporting a range between 30 — 50 % type I muscle fiber proportion (Jennekens et al. 1971; Johnson et al. 1973; Garrett et al. 1984).

In general, the proportion of type I muscle fibers does not differ substantially between athletes and controls (Klitgaard et al. 1990; Jürimäe et al 1996; Fry et al. 2003a; Fry et al. 2003b; Shoepe et al. 2003; Kesidis et al. 2008) but this is not seen entirely consistently (D'Antona et al. 2006).

Greater bodyweight, lower body fat percentage, greater type IIA muscle fiber proportion, and greater force producing ability per unit muscle cross-sectional area are all associated with superior Olympic weightlifting ability among Olympic weightlifters.

Changes in muscle fiber type can be presented as either changes in the proportion of fibers of a given type, or as changes in the absolute or relative cross-sectional area of the fibers.

Velocity - based training preserves type IIX muscle fiber proportion (Pareja - Blanco et al. 2016), while endurance exercise causes a shift from type IIX to type IIA.

Therefore, the trapezius seems to display a mixed to slightly greater proportion of type I muscle fibers in non-strength athletes, while strength athletes may preferentially display a greater proportion of type II muscle fibers.

Moreover, the type IIA fiber proportion was very closely associated with Olympic weightlifting performance.

Among the lower body muscles, the plantar flexors display the highest proportion of type I muscle fibers, and the knee extensors display the lowest proportion of type I muscle fibers, as shown in the chart below, which presents the mean of the data from all currently available studies.

Strength training likely does not lead to a shift in type I to type II muscle fiber proportion.

However, Fry et al. 2003) found that Olympic weightlifters did display higher type IIA fiber proportion and lower type IIX fiber proportion than untrained controls.

In contrast, it seems much more likely that eccentric training leads to a smaller reductions in the proportion of type IIX fibers, compared to concentric training (Colliander & Tesch, 1990; Hortobágyi et al. 1996; Raue et al. 2005; Vikne et al. 2006).

Lower volumes of training may help preserve type IIX fiber proportion.

The shoulders are the only upper body muscle group that displays a tendency towards a higher proportion of type I muscle fibers (Jennekens et al. 1971; Johnson et al. 1973; Humphrey et al. 1982; Tesch et al. 1983; Mavidis et al. 2007; Srinivasan et al. 2007), while the pectoralis major (Johnson et al. 1973; Srinivasan et al. 2007) is mixed - fast twitch.

Overall, the upper body muscles display a tendency towards a lower proportion of type I muscle fibers compared to the lower body muscles.

Overall, it appears that the proportion of type I muscle fibers of the gastrocnemius ranges between 44 — 76 %.

The gastrocnemius muscles display a very high proportion of type I muscle fibers, ranging between 44 — 76 %.

The relative CSA reflects the size of each group of fibers in the sample relative to the others, and this typically involves a similar shift to the proportion, with type IIX fiber area decreasing, and type IIA fiber area increasing.

A higher proportion of type II muscle fibers may therefore be beneficial for strength and power sports.

Tesch et al. (1984) reported that vastus lateralis type II fiber proportion was greater in a combined group of Olympic weightlifters and powerlifters than in a group of endurance athletes, but did not differ from an untrained control group.

The soleus displays an even higher proportion of type I muscle fibers, ranging between 70 — 96 %.

On the other hand, the proportion of type IIX fibers will tend to reduce after both strength training and endurance exercise, while the proportion of type IIA fibers will increase (Farup et al. 2014).

Type IIX muscle fibers are more common in untrained individuals than in trained individuals, and their proportion tends to increase with detraining (Hortobágyi et al. 2000).

They report the proportion of type I muscle fiber in the long and short head of the biceps was 39 % and 37 %, respectively.

High - velocity training also maintains type IIX fiber proportion to a greater extent than low velocity training (Pareja - Blanco et al. 2016), although this effect seems to arise not directly from the velocity of the contraction itself, but rather from the lower volume of work that is typically done (Eftestøl et al. 2016).

They reported that the proportion of type I muscle fiber in the biceps was 39 %.

Studies suggest that the biceps display a predominantly type II fiber proportion.

Based on the orientation and proportion of the fibers that attach on the glenoid labrum (anterior to posterior) the long head of biceps can be classified as type I through IV (I type describing a more posterior attachment, IV describing a more anterior attachment, and II, III being mixed).

Similarly, Gjovagg et al. (2008) performed a cohort study of male and female adults aged 22 years and found that the proportion of type I muscle fiber was 35 %.

Studies to date suggest that the triceps displays a greater proportion of type II muscle fibers than type I muscle fibers.

The erector spinae displays a greater proportion of type I muscle fibers than type II muscle fibers, with type I muscle fiber proportion ranging between 63 — 73 % and 62 — 74 % in the lumbar and thoracic regions, respectively.

The pectoralis major is made up of a higher proportion of type II muscle fibers.

They found that the proportion of type I muscle fiber was 35 %, indicating that the triceps is relatively fast twitch in physical education students who perform well in the shot put.

Haggmark et al. (1979) found that the proportion of type I muscle fiber across the rectus abdominis, internal and external oblique was 55 — 58 %, although there was considerable inter-individual variability.

This belief came from a couple of older studies that showed a slightly greater proportion of type II muscle fibers in the hamstrings compared to other muscles.

They reported that the gluteus medius displayed a slightly greater (42 % type II and 58 % type I) proportion of type I than type II muscle fibers.