I am sure this has been already investigated in scientific literature and I am probably reinventing the wheel, but it must finally come out of academic discussions - only then will the lecturers understand that we, students, need a change.
At WrUT, a lecture normally lasts 1h30 with a 15min break in the middle. The first problem is that many lecturers consider it as optional. Some would ask the students if they want a break but people do not really want to stand out and so the lecture continues. Some do not even bother to ask.
Remaining focused on one topic for one hour is (for me) impossible, and if I loose attention for a brief moment, I also loose track of whatever the professor is saying, which makes my thoughts wander again as my brain finds it boring to listen to something I do not quite understand, and we have a vicious cycle. I know there are students whose ability to concentrate is much better than mine, but there are many more whose experiences are similar to mine. It does not mean we are bad students - I dare say it indicates that the system fails to meet our needs.
It is very easy for the lecturers to forget the student’s perspective, not only in this matter. If you are lecturing, I imagine you must stay alert all the time because otherwise you would simply forget what you were supposed to say next. I have given a few short talks on conferences and seminars - of course it was much more stressful for me than it would be for a seasoned speaker, but it was a completely different experience than being on the other side! Therefore I forgive you, dear professors on whose lectures I could hardly stay awake, and I believe in your good intentions.
A short comparison: here in Cambridge, the lectures are usually around 50min long. In the US - more or less the same, which you can check here or anywhere else - the Internet is now full of lectures recorded at various universities. I asked my friends from India and the answer was the same. However, even at the best unis they can be unreasonably long.
Now, reducing lectures’ duration by half is a good starting point, but we should not stop here. Last year we witnessed the emergence of a few on-line universities (e.g. Coursera, edX.org, Khan Academy). There, the lecture videos can be heavily edited after recording, and guess what: the sequences you are supposed to watch without pausing are between 10 and 25 minutes long! Why would they choose to cut the lecture in four pieces if they could just upload it as it is? Because it yields better results!
Dear deans, rectors, heads of departments: if students at your university have to sit at lectures for more than an hour then the quality of teaching there is poor. Shorten the lectures. The total time may remain the same, all you need to do is split a long lecture on Wednesday afternoon in two shorter ones on Tuesday and Friday - at the same time giving the more motivated students time to revise. Or, if it has to stay the way it is, introduce Zen training for students and we will be able to focus for as long as you want.
Dear lecturers (wherever you are from), here is a simple advice for you: every 15-25 minutes, when you finish talking about one concept and move to another, give the students a break. Ask them an interesting question about what you have just said (you will spot the best students in the class!), demonstrate an experiment, entertain them with a funny story from your life, share the latest gossip from the university, or simply walk out and let them talk for a short while. I guarantee that they will like your course much more than the others!