What are examples of regenerated cellulose fibres and synthetic fibres?

Is there a correlation between workout tempo and the types of muscle fibres exercised?

• If I used a fast tempo during my weightlifting, would the fast twitch Type II B fibres be more directly hit? The fast twitch Type II B fibres fatigue quicker than the Type I and Type II A fibres so I was wondering if it'd be more efficient to do sets with a decent weight with a fast tempo OR more sets with a slightly lighter weight with a slow/controlled tempo. I feel like if I used the slow/controlled tempo, my Type II B fibres wouldn't be worked as much than if I used a faster tempo, unless I did reps and sets to failure :P The exercise I had in mind were lateral raises. Should I be doing them with a fast tempo? And how should the volume be? Thanks

• Answer:

  The general rule of thumb with weight training is: Strength + Size = low reps high weight whilst still being able to maintain good form with slow descents Stamina + Tone = higher reps + lower weight, slow enough to keep good form but fast enough to build a good pump And finally which is more relevant to you: Explosive power = fast ascents pushing hard not focusing too much on descents with a manageable weight (not too heavy, not too light)