Standing desks and stability balls are increasingly popular to increase muscle activity and thereby prevent potential adverse cardiometabolic effects of prolonged sitting. The present study examined the effects of (1) sitting on a stability ball (‘active sitting’) and (2) hourly 10-min standing interruptions during prolonged sitting on postprandial cardiometabolic biomarkers.
Design
Experimental crossover study.
Methods
Twenty healthy-weight males (19.2 ± 0.6 years) participated randomly in three 5-h conditions: (1) sitting on an office chair (SIT), (2) sitting on a stability ball (SIT-ACTIVE) and (3) sitting with hourly 10-min standing interruptions (SIT-STAND). In each condition, participants consumed a standardized mixed meal at baseline. Hourly blood samples and pre/post saliva samples were collected and analyzed for levels of insulin, glucose and cortisol. Pre/post hemodynamic monitoring (middle finger; Nexfin-monitoring) was conducted; heart rate was measured continuously (Polar) and muscle activity (leg and lower-back, Portilab) was measured during periods of sitting (on an office chair and on a stability ball) and standing.
Results
Muscle activity and heart rate during standing periods were significantly higher than during sitting (both SIT and SIT-ACTIVE). Generalized estimating equations revealed no significant difference in any of the biomarkers between the three experimental conditions. Systolic blood pressure was lower during SIT-STAND, while stroke volume was lower during SIT-ACTIVE than during SIT. Although significant, these differences were small, approximating the day-to-day variability in blood pressure and stroke volume.
Conclusions
We conclude that hourly standing interruptions during 5 h prolonged sitting or continuously sitting on a stability ball do not significantly affect postprandial cardiometabolic biomarkers in healthy young men.
Standing is not enough: A randomized crossover study on the acute cardiometabolic effects of variations in sitting in healthy young men. Journal of Science and Medicine in Sports, 04 January, 2019.
If you sit down a lot, chances are that most of the these muscles will be tight:
Hamstrings
Upper Quads
Hip flexors
Biceps
Claves (if you don't have them flat on the floor) (thanks to iwhalewithyou)
(*if you sit completely straight, the list would be over)
(if you instead have more of a hunch over position than the list continues)
Pec major and minor
Abdominal muscles (those might be just slightly tight)
The weak muscles would be:
(Weak muscles doesn't necessarily refer to the muscle being actually weak, as in not developed, the muscle could be strong enough but the opposite muscle might be too tight for it to have an impact on posture)
Glutes
Lower quad
Triceps
(if you have a hunch over position the list will also include)
Lower back
Rhomboids
Lower traps
Erector spinae
In order to cure the imbalances, you will have to stretch the tight muscle and strengthen the weaker ones (sometimes this step in not entirely necessary as I explained above) also actively thinking to stay in a better posture will help.
There are many other postural imbalances that lead to a multitude of different postures, this list will change based on the one your have, however I want to emphasise that those are the muscular imbalances that people who sit down a lot will suffer from.
Edit:I have forgot to mention that you will want to work your rotator cuffs when it come to adjust the shoulder position, however the last exercises in the list in the comments will work on them if done correctly. (thanks to motivationascending)